DE102020120605B4 - Activatable de-esterified fruit fiber, method of manufacture and use - Google Patents

Abstract

A method of producing an activatable deesterified fruit fiber, the method comprising the steps of:(a) providing a raw material containing cell wall material of an edible fruit;(b) digesting the raw material to remove pectin by converting the protopectin to soluble pectin and simultaneously activating it of the fiber by increasing the internal surface area by incubating an aqueous suspension of the raw material at an acidic pH and a temperature of 60°C to 95°C;(c) single or multi-stage separation of the digested material from step (b) from the aqueous liquid;(d) enzymatic or acidic de-esterification of the separated material from step (c), wherein the acidic de-esterification is carried out at a pH between 2.0 and 5.0 and at a temperature between 30 and 55°C;(e ) Washing the de-esterified material from step (d) at least twice with a water-miscible organic solvent and then in each case nd separating the washed material from the water-miscible organic solvent;(f) drying the material from step (e) comprising drying at atmospheric pressure to obtain the activatable deesterified fruit fiber, the activatable deesterified fruit fiber having a water-soluble content of 10% by weight or less pectin and the water-soluble pectin is a low ester pectin having a degree of esterification of less than 50%.

Description

The present invention relates to an activatable de-esterified fruit fibre, in particular a de-esterified citrus or apple fibre, and a process for its production. The invention also relates to the use of the de-esterified fruit fiber as a thickening or structuring agent in various industrial products. Furthermore, the invention relates to a mixture of the activatable de-esterified fruit fiber with a soluble pectin. Ultimately, the invention relates to a food product, feed product, dietary supplement, beverage, cosmetic product, pharmaceutical product or medicinal product which has been produced using the de-esterified fruit fiber according to the invention.

Background of the Invention

Dietary fibers are largely indigestible food components, mostly carbohydrates, which are mainly found in plant foods. For the sake of simplicity, dietary fiber is divided into water-soluble dietary fiber such as pectin and water-insoluble dietary fiber such as cellulose. Fiber is considered an important part of human nutrition.

The consumption of dietary fiber is considered to be good for your health. The water-soluble fiber in the diet increases the volume of the food without significantly increasing the energy content. If they are not sufficiently swollen before ingestion, they absorb more water in the stomach. The resulting increase in volume leads to an increase in the feeling of satiety. In addition, dietary fibers extend the retention time of the chyme in the stomach and intestines. Water-soluble dietary fibers such as pectin bind bile acids from the cholesterol metabolism in the intestine and thus lead to a reduction in cholesterol levels.

It is the soluble fiber that is said to decrease glucose absorption, slow down glucose adsorption and starch processing, and control postprandial serum glucose levels. Anyone who consumes a lot of fiber has a reduced risk of numerous lifestyle diseases, especially obesity, high blood pressure, coronary heart disease (CHD), stroke, diabetes and various gastrointestinal diseases. Accordingly, the German Society for Nutrition e. V. (DGE) as a guideline for the daily intake of at least 30 g fiber.

The use of fruit fibers as roughage in the production of food is becoming increasingly important. One reason for this lies in the fact that the fruit fibers are a mixture of insoluble dietary fibers such as cellulose and soluble dietary fibers such as pectin and thus ideally result in the health-promoting spectrum of effects listed above. By using fruit fibers, the functional properties of food products can be optimized and adjusted in a targeted manner, for example with regard to viscosity, emulsion formation, gel formation, dimensional stability or texture. Fruit fibers can thus replace other unacceptable or even harmful additives in food and, as substances that are not E-classified, lead to simpler product labeling and thus to increased product acceptance.

the WO 01/17 376 A1 relates to a process for the production of roughage with a high water-binding capacity and its use. To this end, it teaches a process for the production of fruit fibers, such as apple fibers or citrus fibers, in which plant components are broken down in an acidic medium and then washed with alcohol (see claim 1, page 7, line 16 to page 8, line 5). However, the process does not include a deesterification step.

the WO 2012/016 190 A1 relates to a process for producing citrus fiber from citrus pomace. The method involves a homogenization step, followed by a washing step with an organic solvent and a final step of solvent removal and drying (see claim 1 and examples 1 to 5 on page 14, line 13 to page 16, line 10). The necessary homogenization, which is preferably high-pressure homogenization (page 4, lines 1 to 2), requires a complex production process in order to obtain fibers with good hydratability and viscosity formation (see page 2, lines 3 to 6).

the WO 94/27451 A1 relates to the production of natural thickening agents from citrus fruit and teaches a process in which an aqueous slurry is prepared from citrus pomace, which is heated to a temperature of 80 to 180°C and then subjected to high-pressure homogenization (see Summary). Here too, in addition to heating, a high-pressure homogenization step is necessary in order to obtain fibers with advantageous rheological properties.

the U.S. 2,754,214 A relates to the manufacture of a low ester pectin hemicellulose product. Here, citrus peels are washed under conditions that retain the fruit's own pectinase, then the pectin is de-esterified in situ with the fruit's own pectinase and washed with acidic alcohol solution to remove divalent cations.

the U.S. 5,567,462 A relates to a pecto-cellulosic product made from whole citrus peel or other materials such as apple. It teaches two methods of making such a product (see column 3, lines 1-12). In the first method, after acidic or alkaline solubilization of the pectin, the dissolved pectin is reprecipitated onto the fiber by adding alcohol, the slurry is neutralized, then the alcohol-water mixture is removed, and the fibers are finally dried after further dehydrating alcohol washing steps. The second method eliminates the alcohol precipitation step and, after acid/alkaline solubilization of the pectin, the slurry is neutralized, crushed and spray dried (col. 3, lines 13-21).

the DE 601 22 522 T2 relates to a process for the production of low methoxyl pectin. Here, a pectin starting material such as citrus peel is treated with a cation-containing preparation to obtain at least a non-calcium-sensitive pectin fraction and a calcium-sensitive pectin fraction. After separating the two fractions, the non-calcium sensitive pectin fraction is subjected to de-esterification.

the DE 187 05 890 T1 relates to methods for producing an activated pectin-containing biomass composition. In this case, citrus peels are used as the starting material, which are first mixed with an aqueous solution of an alcohol and are activated in this mixture by incubation at pH=0.5 to 2.5 and heating to at least 40.degree. In one of the above steps, mechanical energy is applied. Then the activated pectin-containing biomass composition is separated from the mixture.

the U.S. 10,390,552 B2 relates to the production of a highly refined cellulose gel. An isolated, highly refined cellulose fiber is used as the starting material, which is then mixed with at least 0.5% by weight in water, a pH value of less than 9.5 is adjusted by adding a buffer substance and the suspension is brought to the boil with stirring. A cellulose gel is formed by subsequent cooling to below 25°C.

the EP 3 771 346 A1 relates to a method of making a fruit product. A mass of fruit and/or chopped fruit without their peel, core and stalks is used as the starting material. This mass is kept hot at a temperature above 75°C for a period of between 45 minutes and 180 minutes. A fruit product with textural and/or gelling functionality forms. In an optional further step, the fruit product can be de-esterified by enzymatic treatment.

There is therefore a need for new processes for producing fruit fibers and the fruit fibers produced thereby.

The object of the present invention is to improve the prior art or to offer an alternative to it.

Summary of the Invention

1. (a) Bereitstellen eines Rohmaterials, das Zellwandmaterial einer essbaren Frucht, bevorzugt einer Citrusfrucht oder Apfelfrucht enthält;
2. (b) Aufschluss des Rohmaterials zur Entfernung von Pektin durch Überführung des Protopektins in lösliches Pektin und gleichzeitiger Aktivierung der Faser durch Vergrößerung der inneren Oberfläche durch Inkubation einer wässrigen Suspension des Rohmaterials bei einem sauren pH-Wert und einer Temperatur von 60°C bis 95°C;
3. (c) Ein- oder mehrstufige Trennung des aufgeschlossenen Materials aus Schritt (b) von der wässrigen Flüssigkeit;
4. (d) Enzymatische oder saure Entesterung des abgetrennten Materials aus Schritt (c), wobei die saure Entesterung bei einem pH-Wert zwischen 2,0 und 5,0 und bei einer Temperatur zwischen 30 und 55°C erfolgt;
5. (e) Mindestens zweimaliges Waschen des entesterten Materials aus Schritt (d) mit einem organischen wassermischbaren Lösungsmittel und jeweils anschließender Trennung des gewaschenen Materials von dem wassermischbaren organischen Lösungsmittel;
6. (f) Trocknen des Materials aus Schritt (e) umfassend eine Trocknung bei Normaldruck zum Erhalten der aktivierbaren entesterten Fruchtfaser,

wobei die aktivierbare entesterte Fruchtfaser einen Gehalt von 10 Gew.% oder weniger an wasserlöslichem Pektin aufweist und das wasserlösliche Pektin ein niederverestertes Pektin mit einem Veresterungsgrad von weniger als 50% ist.According to a first aspect of the present invention, the task at hand is solved by a method for producing an activatable deesterified fruit fiber, which comprises the following steps:

1. (a) providing a raw material containing cell wall material of an edible fruit, preferably a citrus fruit or apple fruit;
2. (b) Digestion of the raw material to remove pectin by converting the protopectin into soluble pectin and simultaneous activation of the fiber by increasing the internal surface area by incubating an aqueous suspension of the raw material at an acidic pH and a temperature of 60°C to 95°C C;
3. (c) single or multi-stage separation of the digested material from step (b) from the aqueous liquid;
4. (d) enzymatic or acidic de-esterification of the separated material from step (c), wherein the acidic de-esterification is carried out at a pH between 2.0 and 5.0 and at a temperature between 30 and 55°C;
5. (e) washing the de-esterified material from step (d) at least twice with a water-miscible organic solvent and then separating the washed material from the water-miscible organic solvent each time;
6. (f) drying the material from step (e) including drying at atmospheric pressure to obtain the activatable de-esterified fruit fiber,

wherein the activatable de-esterified fruit fiber has a water-soluble pectin content of 10% by weight or less and the water-soluble pectin is a low ester pectin having a degree of esterification of less than 50%.

The production process according to the invention leads to fruit fibers with a large inner surface, which also increases the water-binding capacity and is associated with good viscosity formation. Slight gel formation can also be observed, particularly in applications containing calcium.

These fibers are fibers that can be activated, which have a satisfactory strength due to the partial activation in the manufacturing process. However, in order to obtain the optimal rheological properties such as viscosity, gelation or texturing, the user has to apply additional shearing forces. It is therefore a matter of partially activated fibers, which can, however, be further activated.

The activatable, low-pectin (i.e. water-soluble pectin content ≤ 10% by weight) and low-esterified fruit fiber obtained by the process according to the invention is also referred to as “deesterified fruit fiber” for short within the scope of the invention.

As the inventors have found, the fruit fibers produced using the method according to the invention have good rheological properties. The fibers of the invention can be easily rehydrated in calcium-free water and the advantageous rheological properties are retained even after rehydration.

The production process according to the invention leads to fruit fibers which are largely tasteless and odorless and are therefore advantageous for use in the food sector. The aroma of the other ingredients is not masked and can therefore develop optimally.

The fruit fibers according to the invention are obtained from fruits and are therefore natural ingredients with well-known positive properties.

Plant processing residues such as apple pomace or citrus pomace can be used as raw material in the production process according to the invention. These processing residues are inexpensive, plentiful, and provide a sustainable and ecologically viable source of the fruit fibers of the present invention.

Fruit fibers are established and accepted in the food industry, so that corresponding compositions can be used immediately and internationally without lengthy approval processes.

The invention in detail

The invention relates to processed fruit fibers and a method for their production.

A fruit fiber according to the invention is a plant fibre, ie a fiber isolated from a nonlignified plant cell wall and consisting mainly of cellulose, and which is thereby isolated from a fruit. A fruit is to be understood here as the entirety of the organs of a plant that emerge from a flower, with both the classic fruit fruits and fruit vegetables being included.

In a preferred embodiment, this fruit fiber is selected from the group consisting of citrus fibre, apple fibre, sugar beet fibre, carrot fiber and pea fibre, the plant fiber preferably being a fruit fiber and particularly preferably a citrus fiber or an apple fibre.

An "apple fiber" according to the application is a primarily fibrous component isolated from a nonlignified plant cell wall of an apple and composed primarily of cellulose. The term fiber is somewhat misnomer, because apple fibers do not appear macroscopically as fibers, but are a powdered product. Other components of apple fiber include hemicellulose and pectin.

The apple fiber can be obtained from all cultivated apples (malus domesticus) known to those skilled in the art. Processing residues from apples can advantageously be used here as the starting material. The starting material used can be apple peel, core casing, seeds or fruit pulp or a combination thereof. Apple pomace is preferably used as the starting material, i.e. the pressed residue from apples, which typically also contain the above-mentioned components in addition to the skins.

A "citrus fiber" according to the application is a primarily fibrous component isolated from a nonlignified plant cell wall of a citrus fruit and composed primarily of cellulose. The term fiber is somewhat misnomer because citrus fibers do not appear macroscopically as fibers, but rather represent a powdered product. Other components of citrus fiber include hemicellulose and pectin. The citrus fiber can advantageously be obtained from citrus pulp, citrus peel, citrus vesicles, segmental membranes or a combination thereof.

Citrus fruits and, preferably, processing residues of citrus fruits can be used as raw material for the production of a deesterified citrus fiber. Correspondingly, citrus peel (and here albedo and/or flavedo), citrus vesicles, segmented membranes or a combination thereof can be used as raw material for use in the method according to the invention. Citrus pomace is preferably used as the raw material, ie the pressing residue of citrus fruits, which typically also contain the pulp in addition to the peel.

All citrus fruits known to those skilled in the art can be used as citrus fruits. In a non-limiting manner, the following are listed here by way of example: Tangerine (Citrus reticulata), Clementine (Citrus × aurantium Clementine group, syn.: Citrus clementina), Satsuma (Citrus × aurantium Satsuma group, syn.: Citrus unshiu), Mangshan (Citrus mangshanensis), orange (Citrus × aurantium orange group, syn.: Citrus sinensis), bitter orange (Citrus × aurantium bitter orange group), bergamot (Citrus × limon bergamot group, syn.: Citrus bergamia), grapefruit (Citrus maxima) , grapefruit (Citrus × aurantium grapefruit group, syn.: Citrus paradisi) pomelo (Citrus xaurantium pomelo group), lime (Citrus × aurantiifolia), common lime (Citrus × aurantiifolia, syn.: Citrus latifolia), kaffir lime (Citrus hystrix), Rangpur lime (Citrus × jambhiri), lemon (Citrus × limon lemon group), citron (Citrus medica) and kumquats (Citrus japonica, syn.: Fortunella). The orange (Citrus×aurantium orange group, syn.: Citrus sinensis) and the lemon (Citrus×limon lemon group) are preferred here.

The acid digestion in step (b) of the process serves to remove pectin by converting the protopectin into soluble pectin and at the same time activate the fiber by increasing the internal surface area. Furthermore, the raw material is thermally crushed by the digestion. It disintegrates into fruit fibers as a result of the acidic incubation in an aqueous medium under the influence of heat. This achieves thermal comminution, and a mechanical comminution step is therefore not necessary as part of the manufacturing process. This represents a decisive advantage over conventional fiber manufacturing processes, which in contrast require a shearing step (such as by (high) pressure homogenization) in order to obtain a fiber with sufficient rheological properties.

During digestion, the raw material is present as an aqueous suspension. According to the invention, a suspension is a heterogeneous mixture of substances consisting of a liquid and solids (particles of raw material) finely distributed therein. Since the suspension tends to sedimentation and phase separation, the particles are suitably kept in suspension by shaking or stirring. There is therefore no dispersion in which the particles are comminuted by mechanical action (shearing) in such a way that they are finely dispersed.

To achieve an acidic pH, the person skilled in the art can use any acid or acidic buffer solution known to him. For example, an organic acid such as citric acid can be used.

Alternatively or in combination with this, a mineral acid can also be used. Examples which may be mentioned are: sulfuric acid, hydrochloric acid, nitric acid or sulphurous acid. Nitric acid or sulfuric acid is preferably used.

In the acid digestion in step (b) of the process, the pH of the suspension is between pH=0.5 and pH=4.0, preferably between pH=1.0 and pH=3.5 and particularly preferably between pH= 1.5 and pH = 3.0.

In the case of the acidic digestion, the incubation takes place at a temperature between 60°C and 95°C, preferably between 70°C and 90°C and particularly preferably between 75°C and 85°C.

The incubation takes place over a period of between 60 minutes and 8 hours and preferably between 2 hours and 6 hours.

In the case of the acidic digestion, the aqueous suspension suitably has a dry matter content of between 0.5% by weight and 5% by weight, preferably of between 1% by weight and 4% by weight, and particularly preferably of between 1.5% by weight and 3% by weight.

The aqueous suspension is stirred or shaken during the digestion. This is preferably done in a continuous manner to keep the particles in suspension in suspension.

In step (c) of the process, the digested material is separated from the aqueous solution and thus recovered. This separation takes place as a single-stage or multi-stage separation.

The digested material is advantageously subjected to a multi-stage solid-liquid separation. The first removal of particles is preferably carried out using a decanter and the second removal using a separator. In contrast to a classification process, starting from the aqueous fiber suspension, the solid is separated from the liquid regardless of the particle size.

Optionally, larger particles can also be separated off in step (c). This is preferably done by a classification process. In the context of the present invention, a classification process is understood as meaning the separation of a disperse mixture of solids into fractions according to particle size. In the simplest case, there are two fractions, but two or three particle fractions with a defined particle distribution can also be generated as part of the classification process. The classic method here is sieving.

Separation of particles with a particle size of more than 500 μm, preferably more than 400 μm and most preferably more than 350 μm, is particularly advantageous here. The separation is advantageously carried out with a straining machine or a sieve drum. This removes both coarse-particle contamination of the raw material and insufficiently digested material. The need to perform this optional separation step depends on the strength of the fibrous material to be pulped. While it is regularly necessary for citrus fibers, apple fibers disintegrate into fine fibers during the acidic hydrolysis step, so that this separation step can generally be omitted.

In one embodiment, a sieve drum is used in the classification method, in which the mesh size is set such that the larger particles to be separated occur in the overflow of the sieve and the smaller particles to be processed further occur in the passage through the sieve. The screen overflow can be fed into a new screening process for post-cleaning. Here, the screen overflow is preferably conveyed to the second screen drum by a washing screw. In one embodiment, the sieve overflow is washed with water or an aqueous buffer during transport in the washing screw, so that, for example, adhering pectin can be removed.

Alternatively, wet screening can be used as a screening process.

Those skilled in the art are familiar with numerous screening machines for carrying out classification processes, which he uses according to the fiber particle size present and the fact that a moist or wet mate rial is available, will select. Examples of screening machines are cantilever screening machines, elliptical screening machines, eccentric screening machines, linear screening machines, throw screening machines, flat screening machines, hammer screening machines, air jet screening machines and eddy current machines.

The classification process in step can be carried out during the single-stage or multi-stage separation of the digested material from the aqueous liquid, before this separation or else after the separation from the aqueous liquid.

If the classification process takes place after the one- or multi-stage separation of the digested material from the aqueous liquid, it must be resuspended with an aqueous solution in order to produce an aqueous suspension with a reduced dry matter content, as required by the corresponding classification process.

In the context of the invention, the “aqueous solution” is understood to mean the aqueous liquid used for resuspension and incubation. The mixture of this aqueous solution and the broken down material is referred to as the "incubation batch".

Advantageously, the resuspension is carried out with water as an aqueous solution. The use of an aqueous buffer solution is particularly advantageous here, so that a pH of 3.5 to 5.5, and advantageously of 4.0 to 5.0, results in the suspension. This pH increase, starting from the strongly acidic pH value of the acidic digestion, is carried out in order to provide an optimal pH value for the subsequent enzymatic deesterification. Alternatively, the pH can also be adjusted to the value from 3.5 to 5.5, and advantageously from 4.0 to 5.0, after resuspension.

NaOH, KOH or a Na or K salt such as sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate can be used for this partial neutralization.

Alternatively, a salt solution with an ionic strength of I<0.2 mol/I can also be used as the aqueous solution.

The resuspension is advantageously carried out at a temperature between 10°C and 70°C, preferably between 20°C and 60°C and particularly preferably between 30°C and 50°C.

When resuspending to carry out the classification process, it is advantageous to add so much liquid that the dry matter is between 0.5% by weight and 5% by weight.

More advantageously, the resuspension is carried out with mechanical agitation of the incubation mixture. This is more conveniently done by stirring or shaking the wash mixture.

After the solid-liquid separation and the optional separation of larger particles, according to step (d) the separated, optionally classified material from step (c) is incubated in an incubation mixture with a pectin methyl esterase or subjected to acidic deesterification.

In the event that the material in step (c) was subjected to a classification process in addition to the solid-liquid separation, it is present as a suspension with a low dry matter content (<12% by weight TS) due to the resuspension required for this. The enzyme treatment is then expediently carried out in a stirred tank.

In the event that no classification process was used for the material in step (c), it is present as a result of the solid-liquid separation as a suspension with a high dry matter content (>12% by weight of dry substance). In this case, the enzyme treatment is conveniently carried out in a thick sludge reactor.

The following table gives some examples of commercially available PMEs with their reaction optima: product name Manufacturer optimum Rapidase PEP DSM pH = 4 - 5; T = 50°C Pectinase 872 L biocatalysts pH = 4 - 5; T = 30 - 50°C Fructozyme Flot Erbsloh pH = 3 - 5; T > 15°C

A pectin methyl esterase (abbreviation: PME, EC 3.1.1.11, also: pectin demethoxylase, pectin methoxylase) is a common enzyme in the cell wall of all higher plants and some bacteria and fungi which splits the methyl ester of the pectins and thereby forms poly-galacturonic acid and releases methanol . The PME has been isolated in many isoforms, all of which can be used for enzymatic deesterification according to the invention. The pectin methylesterases have an optimum pH between 2 and 5 and an optimum temperature of 30 to 50°C, with significant enzyme activity already being observed from 15°C, depending on the enzyme.

The duration of the incubation with the pectin methylesterase is between 1 hour and 10 hours, preferably between 2 hours and 5 hours.

In the acidic deesterification in step (d) of the process, the pH of the suspension is between pH=2.0 and pH=5.0. The acidic deesterification according to step (e) can be carried out, for example, at a pH of 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3, 3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9 or 5.0 can be performed.

The acidic de-esterification according to step (d) takes place at a temperature between 30°C and 60°C. It can be carried out, for example, at a temperature of 35°C, 40°C, 45°C, 55°C or 60°C.

In the case of the acidic de-esterification according to step (d), the incubation takes place over a period of between 30 minutes and 10 days and preferably between 2 hours and 6 hours. The acidic digestion according to step (c) can be carried out, for example, over a period of 1.5 h, 2.0 h, 2.5 h, 3.0 h, 3.5 h, 4.0 h, 4.5 h, 5, 0 h, 5.5 h or 6.0 h can be carried out.

After the incubation with the enzyme or the acidic de-esterification according to step (d), a suspension with a low dry substance content (<12 Wt.% TS) is present, a concentration of the deesterified material.

This concentration can take place, for example, by ultracentrifugation or evaporation of the aqueous liquid. This concentration is designed in such a way that the pectin is retained in the material, i.e. it is essentially not separated by the concentration.

In step (e), a washing step then takes place with a water-miscible organic solvent. This involves washing at least twice with a water-miscible organic solvent.

A solvent here means at least one solvent, so that two, three or more water-miscible organic solvents can also be present.

Water-miscible, thermally stable, volatile solvents containing only carbon, hydrogen and oxygen, such as alcohols, ethers, esters, ketones and acetals, are particularly suitable for carrying out the process according to the invention. Ethanol, n-propanol, isopropanol, methyl ethyl ketone, 1,2-butanediol-1-methyl ether, 1,2-propanediol-1-n-propyl ether or acetone are preferably used.

An organic solvent is referred to herein as “water-miscible” when it is in a 1:20 (v/v) mixture with water as a single-phase liquid.

In general, it is expedient to use solvents which are at least 10% by weight water-miscible, have a boiling point below 100° C. and/or have fewer than 10 carbon atoms.

The organic water-miscible solvent is preferably an alcohol, advantageously selected from the group consisting of methanol, ethanol and isopropanol. In a particularly preferred manner it is isopropanol.

The washing step takes place at a temperature between 40°C and 75°C, preferably between 50°C and 70°C and particularly preferably between 60°C and 65°C.

The period of contacting with the water-miscible organic solvent is over a period of between 60 minutes and 10 hours and preferably between 2 hours and 8 hours.

Each water-miscible organic solvent washing step comprises contacting the material with the water-miscible organic solvent for a specified period of time followed by separating the material from the water-miscible organic solvent. A decanter or a press is preferably used for this separation.

When washing with the water-miscible organic solvent, the dry matter in the washing solution is between 0.5% by weight and 15% by weight, preferably between 1.0% by weight and 10% by weight, and particularly preferably between 1.5% by weight .% and 5.0% by weight.

The washing with the water-miscible organic solvent is preferably carried out with mechanical agitation of the washing mixture. The washing is preferably carried out in a tank with an agitator.

When washing with the water-miscible organic solvent, a device for making the suspension more uniform is used in an advantageous manner. This device is preferably a toothed ring disperser.

According to an advantageous embodiment, washing with the water-miscible organic solvent takes place in a countercurrent process.

In one embodiment, washing with the water-miscible organic solvent involves partial neutralization by adding Na or K salts, NaOH or KOH.

When washing with the water-miscible organic solvent, the material can also be decolorized. This decolorization can be done by adding one or more oxidizing agents. The oxidizing agents chlorine dioxide and hydrogen peroxide, which can be used alone or in combination, should be mentioned here as examples.

According to an advantageous embodiment, when washing at least twice with a water-miscible organic solvent, the final concentration of the organic solvent in the solution increases with each washing step. This incrementally increasing proportion of water-miscible organic solvent reduces the proportion of water in the fiber material in a controlled manner, so that the rheological properties of the fibers are retained in the subsequent steps for solvent removal and drying and the partially activated fiber structure does not collapse.

The final concentration of the water-miscible organic solvent is preferably between 60 and 70% by volume in the first washing step, between 70 and 85% by volume in the second washing step and between 80 and 90% by volume in an optional third washing step.

According to the optional step (e1), which takes place between step (e) and (f), the solvent can additionally be reduced by bringing the material into contact with steam. This is preferably done with a stripper in which the material is countercurrently contacted with steam as the stripping gas.

According to an advantageous embodiment, after step (e) or (e1), the material is moistened with water before drying. This is preferably done by introducing the material into a moistening screw and spraying it with water.

In step (f), the washed material from step (e) or the stripped material from step (e1) is dried, the drying comprising drying under normal pressure.

Examples of suitable drying processes using normal pressure are fluidized bed drying, moving bed drying, belt dryers, drum dryers or paddle dryers. Fluid bed drying is particularly preferred here. This has the advantage that the product is dried loosely, which simplifies the subsequent grinding step. In addition, this type of drying avoids damage to the product due to local overheating thanks to the easily adjustable heat input.

The application discloses a vacuum drying for the drying according to step (f). During vacuum drying, the washed material is exposed to a vacuum as a drying item, which reduces the boiling point and thus leads to evaporation of the water even at low temperatures. the Evaporation heat continuously withdrawn from the material to be dried is appropriately tracked from the outside until the temperature is constant. Vacuum drying has the effect of lowering the equilibrium vapor pressure, which favors capillary transport. This has proven to be particularly advantageous for the present apple fiber material, since the activated, open fiber structures and thus the rheological properties resulting therefrom are retained. The vacuum drying preferably takes place at an absolute reduced pressure of less than 400 mbar, preferably less than 300 mbar, further preferably less than 250 mbar and particularly preferably less than 200 mbar.

According to an advantageous embodiment, after the drying in step (f), the method additionally comprises a comminuting, grinding or screening step. This is advantageously designed in such a way that, as a result, 90% by weight of the particles have a particle size of less than 450 μm, preferably a particle size of less than 350 μm and in particular a particle size of less than 250 μm. With this particle size, the fiber is easy to disperse and shows an optimal swelling capacity.

In a second aspect, the invention provides a de-esterified fruit fiber obtained by the manufacturing process of the invention.

The deesterified citrus fiber

In a third aspect, the invention provides an activatable citrus fiber having a pectin content of 10% by weight or less and wherein the pectin has a degree of esterification of less than 50% and is thus a low ester pectin. Within the scope of the invention, this activatable, low-pectin, low-esterified citrus fiber is also referred to as “deesterified citrus fiber”. This de-esterified citrus fiber is obtained by the process of the present invention.

The activatable citrus fiber advantageously has a water-soluble pectin content of between 2% and 8% by weight and more preferably between 2 and 6% by weight. The content of water-soluble pectin in the activatable pectin-containing citrus fiber can be, for example, 2% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight % or 10% by weight.

The de-esterified citrus fiber has advantageous properties in terms of texturing and viscosification behavior, which can be read from the yield point and the dynamic Weissenberg number. Accordingly, the de-esterified citrus fiber may exhibit one or more of the following yield point and dynamic Weissenberg number characteristics, and advantageously exhibit all of these characteristics.

In one embodiment, the deesterified citrus fiber in a 2.5% by weight suspension has a yield point II (rotation) of 0.1-1.5 Pa, advantageously 0.4-1.0 Pa, and particularly advantageously 0. 6 - 0.8 Pa.

Advantageously, the de-esterified citrus fiber in a 2.5% by weight suspension has a yield point II (Cross Over) of 0.1 - 1.0 Pa, advantageously of 0.2 - 0.7 Pa and particularly advantageously of 0.3 - 0.5Pa.

In a 2.5% by weight dispersion, the deesterified citrus fiber can have a yield point I (rotation) of 3.0-7.0 Pa, advantageously of 4.0 to 5.5 Pa and particularly advantageously of 4.3-5. 3 Pa.

In a further embodiment, the de-esterified citrus fiber in a 2.5% by weight dispersion has a yield point I (Cross Over) of 4.0-7.0 Pa, advantageously of 4.5-6.5 Pa and particularly advantageously of 5 .0 - 6.0 Pa.

Advantageously, the de-esterified citrus fiber in a 2.5% by weight suspension has a dynamic Weissenberg number of 7.0-10.0, advantageously 7.5-9.5 and particularly advantageously 8.1-9.1.

Suitably the de-esterified citrus fiber in a 2.5% by weight dispersion has a dynamic Weissenberg number of 7.5-10.0, advantageously 8.0-9.5 and most advantageously 8.3-9.3.

For the de-esterified citrus fiber, the features of the above-described yield point and dynamic Weissenberg number characteristics may optionally also be present in any permutation be combined. Thus, in a specific embodiment, the deesterified citrus fiber according to the invention can have all the characteristics in terms of yield point and dynamic Weissenberg number, this deesterified citrus fiber being obtained by the process according to the invention.

To determine the yield point I (rotation), yield point I (crossover) and the dynamic Weißenberg number in a 2.5% by weight dispersion, the deesterified citrus fiber is prepared as a 2.5% by weight solution according to the method disclosed in the examples dispersed, the measurement takes place after 1 h at 20°C.

To determine the yield point II (rotation), the yield point II (crossover) and the dynamic Weißenberg number in a 2.5% by weight suspension, the deesterified citrus fiber is prepared as a 2.5% by weight solution according to the method disclosed in the examples suspended, the measurement takes place after 1 h at 20°C.

According to an advantageous embodiment, the deesterified citrus fiber has a strength of between 60 g and 240 g, preferably between 120 g and 200 g and particularly preferably between 140 and 180 g in an aqueous 4% by weight suspension.

Preferably, the deesterified citrus fiber has a viscosity of between 550 to 850 mPas, preferably from 600 to 800 mPas, and particularly preferably from 650 to 750 mPas, the deesterified citrus fiber being dispersed in water as a 2.5% by weight solution and the Viscosity is measured at a shear rate of 50 s ^-1 at 20°C.

To determine the viscosity, the citrus fiber is dispersed in demineralized water using the method disclosed in the examples as a 2.5% by weight solution and the viscosity is measured at 20° C. and four shear sections (first and third section = constant profile; second and fourth section = linear ramp; evaluation in each case at a shear rate of 50 s ^-1 ) (rheometer; Physica MCR series, measuring body CC25 (corresponds to Z3 DIN), Anton Paar, Graz, Austria). A de-esterified citrus fiber with this high viscosity has the advantage that smaller amounts of fiber are required to thicken the end product. The fiber also creates a creamy texture.

The de-esterified citrus fiber advantageously has a water binding capacity of more than 24 g/g, preferably more than 26 g/g, particularly preferably more than 28 g/g, and particularly preferably between 28 and 32 g/g. Such an advantageously high water-binding capacity leads to a high viscosity and, as a result, to lower fiber consumption with a creamy texture.

According to one embodiment, the deesterified citrus fiber has a moisture content of less than 15% by weight, preferably less than 10% by weight and particularly preferably less than 8% by weight.

It is also preferred that the de-esterified citrus fiber has a pH of from 5.0 to 6.0 and preferably from 5.2 to 5.7 in 1.0% by weight aqueous solution.

The de-esterified citrus fiber advantageously has a particle size in which at least 90% by weight of the particles are smaller than 450 μm, preferably smaller than 350 μm and in particular smaller than 250 μm.

According to an advantageous embodiment, the deesterified citrus fiber has a lightness value of L*>84, preferably L*>86 and particularly preferably L*>88. The citrus fibers are thus almost colorless and do not lead to significant discoloration of the products when used in food products .

Advantageously, the de-esterified citrus fiber has a dietary fiber content of 80 to 95% by weight.

Due to the acidic extraction step, the pectin content of the citrus fiber has been greatly reduced such that the deesterified citrus fiber has 10% by weight or less of water soluble pectin. Preferably, the de-esterified citrus fiber has less than 8% by weight and more preferably less than 6% by weight of water-soluble pectin. The de-esterified citrus fiber advantageously has a water-soluble pectin content of between 2% and 8% by weight and more preferably between 2 and 6% by weight. The water-soluble pectin content in the deesterified citrus fiber may be, for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% by weight. or 10% by weight.

This residual pectin is low ester pectin due to the subsequent enzymatic deesterification step. According to the invention, a low-esterified pectin is understood to mean a pectin which has a degree of esterification of less than 50%. The degree of esterification describes the percentage of carboxyl groups in the galacturonic acid units of the pectin which are present in esterified form, eg as methyl ester. The degree of esterification can be determined using the method according to JECFA (Monograph 19-2016, Joint FAO/WHO Expert Committee on Food Additives). The combination of depectinization and deesterification thus gives the citrus fiber according to the invention, which is referred to as “deesterified citrus fiber” in the context of the invention.

The deesterified apple fiber

In a fourth aspect, the invention provides an activatable apple fiber having a pectin content of 10% by weight or less and wherein the pectin has a degree of esterification of less than 50% and is thus a low ester pectin. This activatable, low-pectin, low-esterified apple fiber is also referred to as "deesterified apple fiber" for short within the scope of the invention. This de-esterified apple fiber is obtained by the process of the present invention.

The activatable apple fiber advantageously has a water-soluble pectin content of between 2% and 8% by weight and more preferably between 2 and 6% by weight. The content of water-soluble pectin in the activatable pectin-containing apple fiber can be, for example, 2% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight % or 10% by weight.

The deesterified apple fiber has advantageous properties in terms of texturing and viscosification behavior, which can be read from the yield point and the dynamic Weissenberg number. Accordingly, the de-esterified apple fiber may exhibit one or more of the following yield point and dynamic Weissenberg number characteristics, and advantageously exhibit all of these characteristics.

In one embodiment, the deesterified apple fiber in a 2.5% by weight suspension has a yield point II (rotation) of 0.1-1.5 Pa, advantageously 0.4-1.0 Pa, and particularly advantageously 0. 6 - 0.8 Pa.

Advantageously, the de-esterified apple fiber in a 2.5% by weight suspension has a yield point II (Cross Over) of 0.1 - 1.0 Pa, advantageously of 0.2 - 0.7 Pa and particularly advantageously of 0.3 - 0.5Pa.

In a 2.5% by weight dispersion, the de-esterified apple fiber can have a yield point I (rotation) of 3.0-7.0 Pa, advantageously of 4.0 to 5.5 Pa and particularly advantageously of 4.3-5. 3 Pa.

In a further embodiment, the de-esterified apple fiber in a 2.5% by weight dispersion has a yield point I (Cross Over) of 4.0-7.0 Pa, advantageously of 4.5-6.5 Pa and particularly advantageously of 5 .0 - 6.0 Pa.

Advantageously, the de-esterified apple fiber in a 2.5% by weight suspension has a dynamic Weissenberg number of 7.0-10.0, advantageously 7.5-9.5 and particularly advantageously 8.1-9.1.

Suitably the de-esterified apple fiber in a 2.5% by weight dispersion has a dynamic Weissenberg number of 7.5-10.0, advantageously 8.0-9.5 and most advantageously 8.3-9.3.

For the de-esterified apple fiber, the features of the above-described characteristics with regard to yield point and dynamic Weissenberg number can optionally also be combined in any permutation. Thus, in a special embodiment, the deesterified apple fiber according to the invention can have all the characteristics in terms of yield point and dynamic Weissenberg number, with this deesterified apple fiber being obtained by the process according to the invention.

To determine the yield point I (rotation), yield point I (crossover) and the dynamic Weißenberg number in a 2.5% by weight dispersion, the deesterified apple fiber is prepared as a 2.5% by weight solution according to the method disclosed in the examples dispersed, the measurement takes place after 1 h at 20°C.

To determine the yield point II (rotation), the yield point II (crossover) and the dynamic Weißenberg number in a 2.5% by weight suspension, the deesterified apple fiber is prepared as a 2.5% by weight solution according to the method disclosed in the examples suspended, the measurement takes place after 1 h at 20°C.

According to an advantageous embodiment, the de-esterified apple fiber has a strength of between 60 g and 240 g, preferably between 120 g and 200 g and particularly preferably between 140 and 180 g in an aqueous 4% by weight suspension.

Preferably, the deesterified apple fiber has a viscosity of between 550 to 850 mPas, preferably from 600 to 800 mPas, and particularly preferably from 650 to 750 mPas, the deesterified citrus fiber being dispersed in water as a 2.5% by weight solution and the Viscosity is measured at a shear rate of 50 s ^-1 at 20°C.

To determine the viscosity, the apple fiber is dispersed in demineralized water using the method disclosed in the examples as a 2.5% by weight solution and the viscosity is measured at 20°C and four shear sections (first and third section = constant profile; second and fourth section = linear ramp; evaluation in each case at a shear rate of 50 s ^-1 ) (rheometer; Physica MCR series, measuring body CC25 (corresponds to Z3 DIN), Anton Paar, Graz, Austria). A de-esterified apple fiber with this high viscosity has the advantage that smaller amounts of fiber are required to thicken the end product. The fiber also creates a creamy texture.

The de-esterified apple fiber advantageously has a water binding capacity of more than 24 g/g, preferably more than 26 g/g, particularly preferably more than 28 g/g, and particularly preferably between 28 and 32 g/g. Such an advantageously high water-binding capacity leads to a high viscosity and, as a result, to lower fiber consumption with a creamy texture.

According to one embodiment, the de-esterified apple fiber has a moisture content of less than 15% by weight, preferably less than 10% by weight and particularly preferably less than 8% by weight.

It is also preferred that the de-esterified apple fiber has a pH of from 5.0 to 6.0, and preferably from 5.2 to 5.7, in a 1.0% by weight aqueous solution.

The de-esterified apple fiber advantageously has a particle size in which at least 90% by weight of the particles are smaller than 450 μm, preferably smaller than 350 μm and in particular smaller than 250 μm.

According to an advantageous embodiment, the deesterified apple fiber has a lightness value L*>60, preferably L*>61 and particularly preferably L*>62. The apple fibers are thus almost colorless and do not lead to any appreciable discoloration of the products when used in food products .

Advantageously, the de-esterified apple fiber has a dietary fiber content of 80 to 95% by weight.

Due to the acidic extraction step, the pectin content of the apple fiber has been greatly reduced such that the de-esterified apple fiber has 10% by weight or less of water-soluble pectin. Preferably, the de-esterified apple fiber has less than 8% by weight, and more preferably less than 6% by weight, of water-soluble pectin. The de-esterified apple fiber advantageously has a water-soluble pectin content of between 2% and 8% by weight and more preferably between 2 and 6% by weight. The water-soluble pectin content in the deesterified apple fiber may be, for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% by weight by weight. or 10% by weight.

This residual pectin is low ester pectin due to the subsequent enzymatic deesterification step. According to the invention, a low-esterified pectin is understood to mean a pectin which has a degree of esterification of less than 50%. The degree of esterification describes the percentage of the carboxyl groups in the galacturonic acid units of the pectin which are present in the esterified form, e.g. as methyl ester. The degree of esterification can be determined using the JEFCA method (Monograph 19-2016, Joint FAO/WHO Expert Committee on Food Additives). The apple fiber according to the invention, which is referred to as “deesterified apple fiber” in the context of the invention, is thus obtained through the combination of depectinization and deesterification.

In a fifth aspect, the invention relates to the use of the de-esterified fruit fiber according to the invention, which is preferably a de-esterified citrus or apple fibre, as a thickening agent or structuring agent in a food product, a feed product, a beverage or food supplement or in a cosmetic product.

In a sixth aspect the invention relates to a mixture comprising the fruit fiber according to the invention, which is preferably a de-esterified citrus or apple fibre, and a soluble pectin which can be either a low ester or a high ester or low ester amidated pectin or mixtures thereof.

In a seventh aspect, the invention relates to a food product, feed product or beverage made using the de-esterified fruit fiber of the invention, which is preferably a de-esterified citrus or apple fibre.

definitions

A citrus fiber according to the application is a mainly fibrous component isolated from a nonlignified plant cell wall of a citrus fruit and consists mainly of cellulose. The term fiber is somewhat misnomer because citrus fibers do not appear macroscopically as fibers, but rather represent a powdered product. Other components of citrus fiber include hemicellulose and pectin.

A pectin according to the application is defined as a vegetable polysaccharide which, as a polyuronide, essentially consists of α-1,4-glycosidically linked D-galacturonic acid units. The galacturonic acid units are partially esterified with methanol. The degree of esterification describes the percentage of the carboxyl groups in the galacturonic acid units of the pectin which are present in the esterified form, e.g. as methyl ester.

According to the invention, a low-esterified pectin is understood to mean a pectin which has a degree of esterification of less than 50%. The degree of esterification describes the percentage of the carboxyl groups in the galacturonic acid units of the pectin which are present in the esterified form, e.g. as methyl ester. The degree of esterification can be determined using the method according to JECFA (Monograph 19-2016, Joint FAO/WHO Expert Committee on Food Additives).

At this point it should be explicitly pointed out that features of the solutions described above or in the claims and/or figures can also be combined if necessary in order to be able to implement or achieve the explained features, effects and advantages in a cumulative manner.

All features disclosed in the application documents are claimed to be essential to the invention, provided they are new compared to the prior art, either individually or in combination with one another.

It should also be expressly pointed out that in the context of the present patent application, indefinite articles and numbers such as "one", "two" etc. should generally be understood as "at least" information, i.e. as "at least one..." , "at least two..." etc., unless it is expressly stated from the respective context or it is obvious or technically imperative for the person skilled in the art that only "exactly one...", "exactly two..." etc .

Further advantages, special features and expedient developments of the invention result from the subclaims and the following description of preferred exemplary embodiments with reference to the illustrations.

exemplary embodiments

The embodiments shown here only represent examples of the present invention and should therefore not be understood to be limiting. Alternative embodiments contemplated by those skilled in the art are equally encompassed within the scope of the present invention.

1. Description of the manufacturing process using a rough flow diagram

In 1 a method according to the invention for the production of the citrus fiber is shown schematically as a flow diagram. Starting from the citrus pomace 10, the pomace is broken down by hydrolysis 20 by incubation in an acidic solution at 70° to 80°C. This is followed by two separate steps 30a (decanter) and 30b (separator) for the most complete possible separation of all particles from the liquid phase. The separated material is resuspended in step 35 with an aqueous NaOH solution to obtain a suspension with a pH of between 3.0 and 5.0. In step 38, coarse or unbroken particles are then separated by wet sieving using a straining machine. In step 40, the enzymatic de-esterification then takes place by adding a pectin methyl esterase and incubating for 2 to 8 hours at 10 to 60°C. Two alcohol washing steps 50 and 70 are then carried out, each with subsequent solid-liquid separation using decanters 60 and 80 . Finally, in step 100, the fibers are gently dried by means of fluidized bed drying in order to then obtain the citrus fibers 110 according to the invention.

2. Test method for determining the yield point (rotational measurement)

Measuring principle:

This yield point provides information about the structural strength and is determined in the rotation test by increasing the shear stress acting on the sample over time until the sample begins to flow.

Shear stresses that are below the yield point only cause an elastic deformation, which only leads to yielding if the shear stresses are above the yield point. In this determination, this is measured by exceeding a specified minimum shear rate γ̇. According to the present method, the yield point τ _o [Pa] is exceeded at the shear rate γ̇ ≥ 0.1 s ^-1 . Measuring device: Rheometer Physica MCR series (e.g. MCR 301, MCR 101) Measuring system: Z3 DIN or CC25 Measuring cup: CC 27 P06 (ribbed measuring cup) Number of measurement sections: 3 Measuring temperature: 20°C Measurement parameters: 1st section (rest phase): Section Settings: - Default size: shear stress [Pa] - Value: 0 Pa constant - Section duration: 180s - Temperature: 20°C 2nd section (determination of the yield point after rotation measurement): Section Settings: - Default size: shear stress [Pa] - Profile: ramp log. - Start value: 0.1Pa - final value: 80 Pa - Section duration: 180s - Temperature: 20°C

Evaluation:

The yield point τ _ο (unit [Pa] is read in Section 2 and is the shear stress (unit: [Pa]) at which the shear rate is γ̇ ≤ 0.10 s ^-1 for the last time.

The yield point measured with the rotation method is also referred to as “yield point (rotation)”.

The flow limit (rotation) was measured using a fiber suspension (simply stirring the fiber in with a spoon=corresponds to a non-activated fiber) and is also referred to as “yield limit rotation II” within the scope of the invention. The yield point was also measured using a fiber dispersion (stirred in under the action of high shear forces; e.g. with Ultra Turrax = corresponds to an activated fiber) and is also referred to as “yield point rotation I” within the scope of the invention.

3. Test method for determining the yield point (oscillation measurement)

Measuring principle:

This yield point also provides information about the structural strength and is determined in the oscillation test by increasing the amplitude at a constant frequency until the sample is destroyed by the ever-increasing deflection and then begins to flow.

Below the yield point, the substance behaves like an elastic solid, i.e. the elastic parts (G') are above the viscous parts (G"), while when the yield point is exceeded, the viscous parts of the sample increase and the elastic parts decrease.

By definition, the yield point is exceeded for the amplitude when the same number of viscous and elastic components are present G' = G" (Cross Over), the associated shear stress is the corresponding measured value. Measuring device: Rheometer Physica MCR series (e.g. MCR 301, MCR 101) Measuring system: Z3 DIN or CC25 Measuring cup: CC 27 P06 (ribbed measuring cup)

Measurement parameters: Section Settings: - amplitude defaults: deformation - Profile: ramp log. - Value: 0.01 - 1000% - Frequency: 1.0Hz - Temperature: 20°C Evaluation:

With the help of the Rheoplus rheometer software, the shear stress at the cross-over is evaluated after exceeding the linear-viscoelastic range.

The yield point measured using the oscillation method is also referred to as the "cross-over yield point".

The crossover yield point was measured using a fiber suspension (simply stirring in the fiber with a spoon=corresponds to a non-activated fiber) and is also referred to as “crossover II yield point” within the scope of the invention. The yield point was also measured using a fiber dispersion (stirred in under the action of high shear forces; e.g. with Ultra Turrax = corresponds to an activated fiber) and is also referred to as “Cross Over I yield point” within the context of the invention.

Measurement results and their meaning:

If one considers the yield point for the fiber suspension according to the invention stirred in with a spoon (corresponding to a non-activated fiber) with the fiber dispersion according to the invention stirred in with high shear forces, e.g. Ultra Turrax (corresponding to an activated fiber), one can make a statement about the advantage/necessity of activation. The measurement results are summarized in the following table. As expected, the yield point increases in each case due to the shear activation in the dispersion. Due to the relatively low yield point of the fiber suspension with τ _ο II = 0.8 Pa, activation of the fiber is necessary for full implementation of the fiber properties in order to obtain the desired creamy texture. fiber rotation Cross over activation τ _o II [Pa] suspension τ _o I [Pa] dispersion τ _o II[Pa] suspension τ _o I [Pa] dispersion Citrus fiber according to the invention 0.8 3.0 0.6 3.4 necessary

4. Test method for determining the dynamic Weissenberg number

Measuring principle and meaning of the dynamic Weissenberq number:

The dynamic Weißenberg number W' (Windhab E, Maier T, Lebensmitteltechnik 1990, 44: 185f) is a derived quantity in which the elastic components (G') determined in the oscillation test in the linear-viscoelastic range are compared with the viscous components (G") in total ratio: $$W\text{'}=\frac{G\text{'}\left(\omega \right)}{G\text{'}\text{'}\left(\omega \right)}=\frac{1}{tan\mathrm{\delta }}$$

With the dynamic Weißenberg number, one obtains a variable that correlates particularly well with the sensory perception of consistency and can be viewed relatively independently of the absolute strength of the sample.

A high value for W' means that the fibers have built up a predominantly elastic structure, while a low value for W' indicates structures with clearly viscous components. The creamy texture typical of fibers is achieved when the W' values are in the range of approx. 6 - 8, with lower values the sample is judged to be watery (less thick). Material and methods: Measuring device: Rheometer Physica MCR series, e.g. MCR 301, MCR 101 Measuring system: Z3 DIN or CC25 Measuring cup: CC 27 P06 (ribbed measuring cup) Measurement parameters: Section Settings: - amplitude defaults: deformation - Profile: ramp log - Value: 0.01 - 1000% - Frequency: 1.0Hz - Temperature: 20°C

Evaluation:

The phase shift angle δ is read in the linear viscoelastic range. The dynamic Weißenberg number W' is then calculated using the following formula: $$W\text{'}=\frac{1}{tan\mathrm{\delta }}$$

Measurement results and their meaning:

If one considers the dynamic Weißenberg number W' for the fiber suspension according to the invention stirred in with a spoon (corresponding to a non-activated fiber) with the fiber dispersion according to the invention stirred in with high shear forces, e.g. Ultra Turrax (corresponding to an activated fiber), one can make a statement about the texture and beyond about the need for activation. The measurement results are summarized in the following table. With W' values of 7.2 in the suspension and 7.5 for the dispersion, the citrus fiber according to the invention is in the ideal range and thus has an optimal texture. In both cases it has a creamy texture. The results on the dynamic Weißenberg number show that activation of the fiber is not absolutely necessary in order to achieve the desired creamy texture. fiber W' suspension W' dispersion texture Citrus fiber according to the invention 7.2 7.5 creamy with and without activation, viscosity/yield point is regulated by the dosage

5. Test Method for Determining Strength

Execution:

150 ml of distilled water are placed in a beaker. Then stir 6.0 g of citrus fibers or lump-free into the water with a spoon. This fibre-water mixture is allowed to stand for 20 minutes to allow it to swell. The suspension is transferred to a vessel (Ø 90 mm). Then the strength is measured by the following method. Measuring device: Texture Analyzer TA-XT 2 (Stable Micro Systems, Godalming, UK) Test method/option: Measurement of the force in the direction of compression / simple test Parameter: - Test Speed: 1.0mm/s - Travel: 15.0mm/s measuring tool: P/50

According to the present method, the strength corresponds to the force that the measuring body needs to penetrate 10 mm into the suspension. This force is read from the force-time diagram.

6. Test method for determining grain size

Measuring principle:

In a screening machine, a set of screens, the mesh size of which constantly increases from the bottom screen to the top, is arranged one above the other. The sample is placed on the top sieve - the one with the largest mesh size. The sample particles with a diameter larger than the mesh size remain on the sieve; the finer particles fall through to the next sieve. The proportion of the sample on the different sieves is weighed out and reported as a percentage.

Execution:

The sample is weighed to two decimal places. The screens are provided with screening aids and built up one on top of the other with increasing mesh sizes. The sample is quantitatively transferred to the top sieve, the sieves are clamped and the sieving process proceeds according to defined parameters. The individual sieves are weighed with sample and sieve aid and empty with sieve aid. Should be at one product, only a limit value in the grain size spectrum is checked (e.g. 90% < 250 µm), then only a sieve with the corresponding mesh size is used. measurement specifications sample amount: 15g sieving aids: 2 per sieve tray screening machine: AS 200 digit, Retsch GmbH sieve movement: three dimensional vibration level: 1.5mm sieving time: 15 minutes

The screen construction consists of the following mesh sizes in µm: 1400, 1180, 1000, 710, 500, 355, 250 followed by the bottom.

The grain size is calculated using the following formula: $$Anteip\mathrm{right}OSiebin\%=\frac{A\mathrm{and}swaaGeinGa\mathrm{and}f\mathrm{i.e}emSieb\times 100}{P\mathrm{right}ObeeinwaaGeinG}$$

7. Preparation of a 2.5% by weight fiber dispersion

• 2,50 g Faserstoffe
• 97,5 g demineralisiertes Wasser (Raumtemperatur)
• Einstreudauer: 15 Sekunden

Recipe:

• 2.50 g fibers
• 97.5 g demineralized water (room temperature)
• Sprinkle duration: 15 seconds

In a 250 ml beaker, the respective amount of the. Water (room temperature) presented. The exactly weighed amount of fibers is with the agitator running (Ultra Turrax) at 8000 rpm. (Level 1) slowly sprinkled directly into the stirring suction. The sprinkling time depends on the amount of fibers, it should last 15 seconds per 2.5 g sample. Then the dispersion is exactly 60 seconds at 8000 rpm. (Stage 1) stirred. If the sample is to be used to determine the viscosity or to determine the yield point I (rotation), the yield point I (crossover) or to determine the dynamic Weißenberg number, it is placed in a water bath at 20°C.

To measure the viscosity or to measure the yield point I (rotation), the yield point I (crossover) or to measure the dynamic Weißenberg number, the sample is carefully filled into the measuring system of the rheometer after exactly 1 hour and the respective measurement is started. If the sample settles, it is carefully stirred with a spoon immediately before filling.

8. Preparation of a 2.5% by weight fiber suspension

• 2,50 g Faserstoffe
• 97,5 g demineralisiertes Wasser (Raumtemperatur)

Recipe:

• 2.50 g fibers
• 97.5 g demineralized water (room temperature)

In a 250 ml beaker, the respective amount of the. Water (room temperature) presented. The precisely weighed amount of fibers is slowly sprinkled in while stirring constantly with a plastic spoon. Then the suspension is stirred until all the fibers are wetted with water. If the sample is to be used to determine viscosity or yield point II (rotation), yield point II (crossover) or to determine the dynamic Weißenberg number, it is placed in a water bath at 20°C.

To measure the viscosity or to measure the yield point II (rotation), the yield point II (crossover) or to measure the dynamic Weißenberg number, the sample is carefully placed in the measuring system of the rheometer is filled and the respective measurement is started. If the sample settles, it is carefully stirred with a spoon immediately before filling.

9. Test method for determining the water binding capacity

Procedure for water binding capacity of non-pretreated samples:

The sample is allowed to swell with an excess of water at room temperature for 24 hours. After centrifugation and subsequent decanting of the supernatant, the water binding capacity in g H2O/g sample can be determined gravimetrically. The pH value in the suspension must be measured and documented.

The following parameters must be observed: Sample weight: - plant fiber: 1.0g (in centrifuge tube) - water addition: 60ml - centrifugation: 4000g - centrifugation time 10 mins 20 minutes after the start of centrifugation (or 10 minutes after the end of centrifugation), the supernatant water is separated from the swollen sample. The sample with the bound water is weighed out.

The water binding capacity (WBV) in g H ₂ O / g sample can now be calculated using the following formula: $$\text{WBV}\left({\text{g H}}_2\text{O}/\text{g sample}\right)=\frac{\text{Sample with bound water}\left(\text{G}\right)-1.0\text{G}}{1.0\text{G}}$$

10. Test method for determining viscosity

Measuring device: Physica MCR series (e.g. MCR 301, MCR 101) Measuring system: Z3 DIN or CC25 (Note: The measuring systems Z3 DIN and CC25 are identical measuring systems) Number of Sections: 4

Measurement parameters:

1st section: Section Settings: - Default size: Shear rate [s ^_1 ] - Profile: constant - Value: 0s ^-1 - Section duration: 60s - Temperature: 20°C 2nd section: Section Settings: - Default size: Shear rate [s ^-1 ] - Profile: ramp left - Value: 0.1 - 100s ^-1 - Section duration: 120s - Temperature: 20°C 3rd section: Section Settings: - Default size: Shear rate [s ^-1 ] - Profile: constant - Value: 100s ^-1 - Section duration: 10s - Temperature: 20°C 4th section: Section Settings: - Default size: Shear rate [s ^-1 ] - Profile: ramp left - Value: ^100-0.1s -1 - Section duration: 120s - Temperature: 20°C

Evaluation:

The viscosity (unit [mPas]) is read as follows: 4th section at = 50 s ^-1

11. Test method for determining the degree of esterification

This method corresponds to the JECFA (Joint FAO/WHO Expert Committee on Food Additives) published method. In contrast to the JECFA method, the deashed pectin is not dissolved in the cold but heated. Isopropanol is used as the alcohol instead of ethanol.

12. Test method for determining dietary fiber content

This method is substantially consistent with the method published by the AOAC (Official Method 991.43: Total, Soluble and Insoluble Dietary Fiber in Foods; Enzymatic-Gravimetric Method, MES-TRIS Buffer, First Action 1991, Final Action 1994.). Only isopropyl alcohol was used here instead of ethanol.

13. Test method for determining moisture and dry matter

Principle:

The moisture content of the sample is understood to mean the decrease in mass determined according to defined conditions after drying. The moisture content of the sample is determined by means of infrared drying using the Sartorius MA-45 moisture analyzer (from Sartorius, Goettingen, Germany).

Execution:

Approximately 2.5 g of the fiber sample is weighed into the Sartorius moisture analyzer. The settings of the device can be found in the corresponding factory measurement specifications. For determination, the samples should be at about room temperature. The moisture content is automatically given by the device as a percentage [% M]. The dry matter is automatically given by the device as a percentage [% S].

14. Test method for determining color and brightness

Principle:

The color and brightness measurements are made with the Minolta Chromameter CR 300 or

• Die Farbtöne liegen auf dem Außenmantel des Farbkörpers, die Helligkeit verändert sich auf der senkrechten Achse und der Sättigungsgrad verläuft horizontal. Bei Verwendung des L*a*b*-Messsystems (sprich L-Stern, a-Stern, b-Stern) steht L* für die Helligkeit, während a* und b* sowohl den Farbton als auch die Sättigung angeben. a* und b* nennen die Positionen auf zwei Farbachsen, wobei a* der Rot-Grün-Achse und b* der Blau-Gelb-Achse zugeordnet ist. Für die Farbmessanzeigen wandelt das Gerät die Normfarbwerte in L*a*b*-Koordinaten um.

CR 400 carried out. The spectral properties of a sample are determined using standard color values. The color of a sample is described in terms of hue, lightness and saturation. With these three basic properties, the color can be represented three-dimensionally:

• The hues lie on the outer shell of the color body, the lightness varies on the vertical axis and the degree of saturation runs horizontally. Using the L*a*b* measurement system (say L-star, a-star, b-star), L* represents lightness, while a* and b* represent both hue and saturation. a* and b* indicate the positions on two color axes, where a* is assigned to the red-green axis and b* to the blue-yellow axis. For the color measurement displays, the device converts the standard color values into L*a*b* coordinates.

Carrying out the measurement:

The sample is sprinkled on a white sheet of paper and leveled with a glass stopper. For the measurement, the measuring head of the chromameter is placed directly on the sample and the trigger is pressed. A triplicate measurement is carried out on each sample and the mean value is calculated. The L*, a*, b* values are specified by the device with two decimal places.

The embodiments shown here only represent examples of the present invention and should therefore not be understood to be limiting. Alternative embodiments contemplated by those skilled in the art are equally encompassed within the scope of the present invention.

15. Test method for the determination of water-soluble pectin in fibrous samples

Principle:

The pectin contained in fibrous samples is converted into the liquid phase by means of an aqueous extraction. By adding alcohol, the pectin is precipitated from the extract as an alcohol insoluble substance (AIS).

Extraction:

10.0 g of the sample to be examined are weighed into a glass bowl. 390 g boiling dist. Water is placed in a beaker and the previously weighed sample is stirred in using an Ultra-Turrax for 1 minute at the highest setting.

The sample suspension, which has been cooled to room temperature, is divided into four 150 ml centrifuge beakers and centrifuged at 4000×g for 10 min. The supernatant is collected. The sediment from each beaker is resuspended in 50 g distilled water and centrifuged again at 4000×g for 10 min. The supernatant is collected, the sediment is discarded.

The combined centrifugates are added to about 4 l of isopropanol (98%) to precipitate the alcohol-insoluble substance (AIS). After ½ hour, it is filtered through a filter cloth and the AIS is pressed off manually. The AIS is then added to about 3 l of isopropanol (98%) in the filter cloth and loosened up by hand using gloves.

The squeezing process is repeated, the AIS is removed quantitatively from the filter cloth, loosened up and dried in a drying cabinet at 60° C. for 1 hour.

The pressed, dried substance is weighed out to the nearest 0.1 g to calculate the Alcohol Insoluble Substance (AIS).

Calculation:

The water-soluble pectin is calculated based on the fibrous sample using the following formula, with the water-soluble pectin occurring as an alcohol-insoluble substance (AIS): $$AISin\mathrm{i.e}e\mathrm{right}P\mathrm{right}ObeinGew.\%\left(\frac{G}{100G}\right)=\frac{Get\mathrm{right}OckneteAIS\left[G\right]\times 100}{P\mathrm{right}ObeneinwaaGeinG}$$

Reference List

10

citrus pomace

20

Hydrolysis (digestion) by incubation in an acidic environment

30a

1. Solid-liquid separation decanter

30b

2. Solid-Liquid Separation Separator

35

Resuspension with diluted NaOH _aq solution

38

Separation of coarse and unbroken particles

40

Enzymatic deesterification

50

1. Washing with alcohol

60

solid-liquid separation

70

2. Washing with alcohol

80

solid-liquid separation

100

fluid bed drying

110

Obtained deesterified citrus fiber

Claims (33)

A method of making an activatable de-esterified fruit fiber, the method comprising the steps of: (a) providing a raw material containing cell wall material of an edible fruit; (b) Digestion of the raw material to remove pectin by converting the protopectin into soluble pectin and simultaneous activation of the fiber by increasing the internal surface area by incubating an aqueous suspension of the raw material at an acidic pH and a temperature of 60°C to 95°C C; (c) Single or multi-stage separation of the digested material from step (b) from the aqueous liquid; (d) enzymatic or acidic de-esterification of the separated material from step (c), wherein the acidic de-esterification is carried out at a pH between 2.0 and 5.0 and at a temperature between 30 and 55°C; (e) washing the de-esterified material from step (d) at least twice with a water-miscible organic solvent and then separating the washed material from the water-miscible organic solvent each time; (f) drying the material from step (e) comprising drying at normal pressure to obtain the activatable deesterified fruit fiber, wherein the activatable deesterified fruit fiber has a water-soluble pectin content of 10% by weight or less and the water-soluble pectin is a low ester pectin with a Degree of esterification is less than 50%. procedure according to claim 1 , characterized in that in step (c) there is an additional separation of larger particles by a classification process and the de-esterified material from step (d) is concentrated before step (e) by means of ultrafiltration or evaporation of the liquid. procedure according to claim 1 or 2 , characterized in that between step (e) and (f) the following step is carried out: (e1) additional removal of the organic solvent by contacting the washed material from step (e) with steam. procedure according to claim 1 until 3 , characterized in that the raw material is a residue from the processing of citrus fruits and is preferably a citrus pomace. Method according to any one of the preceding claims, characterized in that the raw material is selected from the group consisting of citrus peel, citrus albedo, citrus flavedo, citrus vesicles, citrus membrane and citrus pomace, and is preferably citrus pomace. Method according to one of the preceding claims, characterized in that the digestion in step (b) satisfies one or more of the following conditions: i. use of an organic acid, in particular citric acid; ii. Use of a mineral acid, in particular sulfuric acid, hydrochloric acid, nitric acid or sulphurous acid, nitric acid being preferred; iii. the pH of the suspension is between pH=0.5 and pH=4.0, preferably between pH=1.0 and pH=3.5 and particularly preferably between pH=1.5 and pH=3.0; IV. the incubation takes place at a temperature between 70°C and 90°C and more preferably between 75°C and 85°C; v. the incubation takes place over a period of between 60 minutes and 8 hours, preferably between 2 hours and 6 hours; vi. the suspension has a dry matter content of between 0.5% and 5% by weight, preferably between 1% and 4% by weight, and more preferably between 1.5% and 3% by weight; vii. the suspension is stirred or shaken during the digestion. Process according to one of the preceding claims, characterized in that the single-stage or multi-stage separation of the digested material from the aqueous liquid in step (c) includes the most complete possible separation of particles. procedure according to claim 7 , whereby the separation preferably takes place with a decanter, a separator or a belt press. Method according to one of the preceding claims, characterized in that the classification process in step (c) is carried out with the aid of a screening machine, which is preferably selected from the group comprising a cantilever screening machine, elliptical screening machine, eccentric screening machine, linear screening machine, throw screening machine, plane screening machine, hammer screening machine, air jet screening machine, eddy current machine and drum screening machine. Method according to one of the preceding claims, characterized in that the classification process in step (c) involves the separation of particles with a particle size of more than 500 µm, preferably with a particle size of more than 400 µm and particularly preferably with a particle size of more than 350 µm included. Process according to one of the preceding claims, characterized in that the classification process in step (c) takes place before, during or after the single-stage or multi-stage separation of the broken down material from the liquid in step (c). A method according to any one of the preceding claims, characterized in that the material resulting from the classification process in step (c) is resuspended prior to the enzymatic treatment. procedure according to claim 12 , characterized in that resuspending the classified material satisfies one or more of the following conditions: i. The aqueous solution is water; an aqueous buffer solution or an aqueous base solution ii. The aqueous solution is a salt solution with an ionic strength of I < 0.2 mol / I; iii. The resuspension takes place at a temperature of between 10°C and 70°C, preferably between 20°C and 60°C and more preferably between 30°C and 50°C; IV. Resuspension results in a suspension having a pH of between 3.5 to 5.5 and preferably between 4.0 to 5.0; v. the dry matter in the suspension for the citrus fiber is between 0.5% by weight and 12% by weight, preferably between 1.5% by weight and 10% by weight, and particularly preferably between 3% by weight and 8% by weight. %; vi. the dry matter in the suspension for the apple fiber is between 5% by weight and 25% by weight, preferably between 10% by weight and 20% by weight, and particularly preferably between 12.5% by weight and 17.5% by weight. %; vii. Resuspension is carried out with stirring or shaking. Process according to one of the preceding claims, characterized in that the enzymatic de-esterification in step (d) satisfies one or more of the following conditions: i. A pectin methylesterase is added to the suspension as an enzyme; ii. The incubation with the pectin methylesterase takes place for a period of 1-10 hours and is preferred from 2 to 5 hours; iii. The enzymatic de-esterification takes place at a temperature of between 10°C and 70°C, preferably between 20°C and 60°C and particularly preferably between 30°C and 50°C; IV. The enzymatic de-esterification is carried out at a pH of between 3.5 to 5.5 and preferably between 4.0 to 5.0; v. the dry mass of the material freed from coarse and unbroken particles in the incubation mixture is between 0.5% by weight and 12% by weight, preferably between 1.5% by weight and 10% by weight, and particularly preferably between 3% by weight .% and 8% by weight; vi. The enzymatic de-esterification is carried out while stirring or shaking the incubation mixture; vii. In the case of enzymatic treatment of a material suspension with a dry substance content > 12% by weight TS, the enzyme treatment takes place in a high-density reactor; viii. In the case of enzymatic treatment of a material suspension with a dry substance content of < 12% by weight TS, the enzyme treatment takes place in a stirred tank. Method according to one of the preceding claims, characterized in that the washing at least twice with a water-miscible organic solvent in step (e) satisfies one or more of the following conditions: i. The water-miscible organic solvent is an alcohol and is preferably selected from the group consisting of methanol, ethanol and isopropanol; ii. The washing step takes place at a temperature between 40°C and 75°C, preferably between 50°C and 70°C and more preferably between 60°C and 65°C; iii. The period of contacting with the water-miscible organic solvent takes place over a period of between 60 minutes and 10 hours, preferably between 2 hours and 8 hours; IV. Each washing step involves separating the solid residue from the water-miscible organic solvent, preferably using a decanter or a press; v. the dry matter in the washing solution of between 0.5% and 15% by weight, preferably between 1.0% and 10% by weight, and particularly preferably between 1.5% and 5.0% by weight .% is; vi. the washing is carried out in a tank with an agitator, vii. during washing, a device is used to make the suspension more uniform, which is preferably a toothed ring disperser; viii. the washing is carried out in a counter-current process; ix. during the washing a partial neutralization takes place by adding NaOH or KOH or Na or K salts; x. During washing, the residue is decolorized by adding one or more oxidizing agents, for example by adding chlorine dioxide and/or hydrogen peroxide. Method according to one of the preceding claims, characterized in that in the at least twice washing with a water-miscible organic solvent according to step (e), the final concentration of the water-miscible organic solvent in the solution increases with each washing step, preferably in the first washing step between 60 to 70% by volume, in the second washing step between 70 and 85% by volume and in an optional third washing step between 80 and 90% by volume. Process according to any one of the preceding claims, characterized in that after the drying in step (f) the process additionally comprises a comminution, milling or sieving step, preferably at least 90% by weight of particles smaller than 250 µm being obtained. Activatable de-esterified fruit fibre, characterized in that the activatable de-esterified fruit fibre, by a method according to any one of Claims 1 until 17 and is an activatable deesterified citrus fiber or an activatable deesterified apple fiber. Activatable deesterified citrus fiber according to Claim 18 , characterized in that the activatable de-esterified citrus fiber has one or more of the following rheological properties: • A yield point II (rotation) in a 2.5% by weight fiber suspension in demineralized water of 0.1 - 1.5 Pa, advantageously of 0.4 - 1.0 Pa and most advantageously from 0.6 - 0.8 Pa; • A yield point II (Cross Over) in a 2.5% by weight fiber suspension in demineralized water of 0.1 - 1.0 Pa, advantageously 0.2 - 0.7 Pa and particularly advantageously 0.3 - 0 .5 Pa; A yield point I (rotation) in a 2.5% by weight fiber dispersion in demineralized water of 3.0 - 7.0 Pa, advantageously of 4.0 - 5.5 Pa and particularly advantageously of 4.3 - 5, 3 Pa; • A yield point I (Cross Over) in a 2.5% by weight fiber dispersion in demineralized water of 4.0 - 7.0 Pa, advantageously from 4.5 - 6.5 Pa and most advantageously from 5.0 - 6.0 Pa; • A dynamic Weissenberg number in a 2.5% by weight fiber suspension in demineralized water of 7.0-10.0, advantageously 7.5-9.5 and particularly advantageously 8.1-9.1; • A dynamic Weißenberg number in a 2.5% by weight fiber dispersion in demineralized water of 7.5-10.0, advantageously of 8.0-9.5 and particularly advantageously of 8.3-9.3; • has a strength in a 4% by weight aqueous suspension of between 60 g and 240 g, preferably between 120 g and 200 g and more preferably between 140 and 180 g; • has a viscosity of 550 to 850 mPas, preferably 600 to 800 mPas, and particularly preferably 650 to 750 mPas, the activatable deesterified citrus fiber being dispersed in water as a 2.5% by weight solution and having the viscosity with a shear rate of 50 s ^-1 is measured at 20°C; • a water binding capacity of more than 24 g/g, preferably more than 26 g/g, particularly preferably more than 28 g/g, and particularly preferably between 28 and 32 g/g. Activatable de-esterified citrus fiber according to any one of claims 18 or 19 , characterized in that the activatable de-esterified citrus fiber has a moisture content of less than 15% by weight, preferably less than 10% by weight and particularly preferably less than 8% by weight. Activatable de-esterified citrus fiber according to any one of claims 18 until 20 , characterized in that the activatable de-esterified citrus fiber has a pH of 5.0 to 6.0 and preferably 5.2 to 5.7 in a 1.0% by weight aqueous solution. Activatable de-esterified citrus fiber according to any one of claims 18 until 21 , characterized in that the activatable de-esterified citrus fiber has a grain size in which at least 90% by weight of the particles are smaller than 450 µm, preferably at least 90% by weight of the particles are smaller than 350 µm and particularly preferably at least 90% by weight of the Particles are smaller than 250 µm. Activatable de-esterified citrus fiber according to any one of claims 18 until 22 , characterized in that the activatable de-esterified citrus fiber has a lightness value L*> 84, preferably L*> 86 and particularly preferably L*> 88. Activatable de-esterified citrus fiber according to any one of claims 18 until 23 , characterized in that the activatable de-esterified citrus fiber has a dietary fiber content of 80 to 95% by weight. Activatable de-esterified apple fiber according to Claim 18 , characterized in that the activatable de-esterified apple fiber has one or more of the following rheological properties: • A yield point II (rotation) in a 2.5% by weight fiber suspension in demineralized water of 0.1 - 1.5 Pa, advantageously of 0.4 - 1.0 Pa and most advantageously from 0.6 - 0.8 Pa; • A yield point II (Cross Over) in a 2.5% by weight fiber suspension in demineralized water of 0.1 - 1.0 Pa, advantageously 0.2 - 0.7 Pa and particularly advantageously 0.3 - 0 .5 Pa; A yield point I (rotation) in a 2.5% by weight fiber dispersion in demineralized water of 3.0 - 7.0 Pa, advantageously of 4.0 - 5.5 Pa and particularly advantageously of 4.3 - 5, 3 Pa; A yield point I (Cross Over) in a 2.5% by weight fiber dispersion in demineralized water of 4.0-7.0 Pa, advantageously 4.5-6.5 Pa and particularly advantageously 5.0-6 .0 Pa; • A dynamic Weissenberg number in a 2.5% by weight fiber suspension in demineralized water of 7.0-10.0, advantageously 7.5-9.5 and particularly advantageously 8.1-9.1; • A dynamic Weißenberg number in a 2.5% by weight fiber dispersion in demineralized water of 7.5-10.0, advantageously of 8.0-9.5 and particularly advantageously of 8.3-9.3; • has a strength in a 4% by weight aqueous suspension of between 60 g and 240 g, preferably between 120 g and 200 g and more preferably between 140 and 180 g; • has a viscosity of 550 to 850 mPas, preferably 600 to 800 mPas, and particularly preferably 650 to 750 mPas, the activatable deesterified apple fiber being dispersed in water as a 2.5% by weight solution and the viscosity being a shear rate of 50 s ^-1 is measured at 20°C; • a water binding capacity of more than 24 g/g, preferably more than 26 g/g, particularly preferably more than 28 g/g, and particularly preferably between 28 and 32 g/g. Activatable de-esterified apple fiber according to any one of claims 18 or 25 , characterized in that the activatable de-esterified apple fiber has a moisture content of less than 15% by weight, preferably less than 10% by weight and particularly preferably less than 8% by weight. Activatable de-esterified apple fiber according to any one of claims 18 , 25 or 26 , characterized in that the activatable de-esterified apple fiber has a pH of 5.0 to 6.0 and preferably 5.2 to 5.7 in a 1.0% by weight aqueous solution. Activatable de-esterified apple fiber according to any one of claims 18 or 25 until 27 , characterized in that the activatable de-esterified apple fiber has a particle size in which at least 90% by weight of the particles are smaller than 450 µm, preferably at least 90% by weight of the particles are smaller than 350 µm and particularly preferably at least 90% by weight of the Particles are smaller than 250 µm. Activatable de-esterified apple fiber according to any one of claims 18 or 25 until 28 , characterized in that the activatable de-esterified apple fiber has a lightness value L* > 60, preferably L* > 61 and particularly preferably L* > 62. Activatable de-esterified apple fiber according to any one of claims 18 or 25 until 29 , characterized in that the activatable de-esterified apple fiber has a dietary fiber content of 80 to 95% by weight. Use of the activatable deesterified citrus fiber according to one of claims 18 until 24 or the activatable de-esterified apple fiber according to any one of claims 18 or 25 until 30 as a thickening or structuring agent in a food product, a feed product, a beverage, a dietary supplement, a cosmetic product, a pharmaceutical product or a medical device. Use of an activatable deesterified fruit fiber according to Claim 18 together with a soluble pectin in a mixture wherein the soluble pectin is preferably a low esterified pectin, a high esterified pectin, a low esterified amidated pectin or a mixture thereof, and wherein the activatable deesterified fruit fiber is advantageously an activatable deesterified citrus fiber according to any one of claims 18 until 24 or an activatable de-esterified apple fiber according to any one of claims 18 or 25 until 30 is. Use of the activatable deesterified fruit fiber according to Claim 18 in a food product, dietary supplement, feed product, beverage, cosmetic product, pharmaceutical product or medical device, wherein the activatable deesterified fruit fiber is advantageously an activatable deesterified citrus fiber according to any one of claims 18 until 24 or an activatable de-esterified apple fiber according to any one of claims 18 or 25 until 30 is.

Images