ES2940363A1 - PROCESS TO PREPARE CITRUS FIBERS FROM A CITRUS FRUIT (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Process for preparing citrus fibers from a citrus fruit. The invention is directed to a process for preparing citrus fibers from a citrus fruit comprising a flavedo, albedo and juice vesicles, comprising the following steps: (a) subjecting the citrus fruit or a part of the citrus fruit to a homogenization treatment to obtain a homogenized fraction, (b) contacting the homogenized fraction with an organic solvent to obtain an organic solvent washed citrus fraction, and (c ) separating the organic solvent and water from the washed citrus fraction with organic solvent to obtain citrus fiber, where the citrus fruit is of the Citrus aurantium species. (Machine-translation by Google Translate, not legally binding)

Description

DESCRIPTION

PROCESS TO PREPARE CITRUS FIBERS FROM A

CITRUS FRUIT

The invention is directed to a process for preparing citrus fibers from a citrus fruit that comprises a homogenization step, a washing step with an organic solvent, and a drying step.

Said process is described in the document WO12016190. A process is described where citrus fibers are prepared from citrus pulp. Citrus is the pectinaceous and cellulosic material contained in the inner part of a citrus fruit that contains juice. It is a co-product of the orange juice industry that comes from the mechanical extraction of the juice. A process is illustrated that includes a pressure homogenizer with a feed pressure of 70,000 kPa (700 bar). The homogenized fraction is contacted with ethanol, and with ethanol and water. Subsequently, a dry cake is obtained in a screw press, which is ground and dried in a vacuum desiccator to recover an orange pulp fiber.

WO2018/119058 describes a process for preparing citrus fiber from waste citrus peel, where the citrus peel was subjected to a depectinization process. Document WO2012/016190 describes a process for preparing citrus fiber from citrus pulp. Document WO2013/109721 describes a process for preparing citrus fiber from citrus peel.

US4526794 describes a process for preparing a citrus fiber, known as albedo thickener, which has a water holding capacity of 10 to 20 grams of water per gram of albedo thickener. albedo. In this process, the albedo of a citrus peel is shaved off and separated from the flavedo. The albedo is subsequently subjected to a process consisting of washing with isopropanol.

Document WO2017/023722 describes a citrus fiber that has a high Water Retention Capacity (CRA). A high water retention capacity is advantageous when the fibers are used as texturizing additives, for example, in food products. A high CRA refers to a high free specific area for binding with water upon rehydration and dispersion. This, in turn, provides the fibers with improved thickening capabilities, good stability, and the ability to create optimal food textures.

Therefore, there is a continuing desire to provide a citrus fiber that has a high water holding capacity.

The applicants verified that citrus fibers with a high water retention capacity are obtained when the fruit of the Citrus aurantium species is used as raw material to prepare citrus fibers.

Furthermore, the invention is also directed to the following process. Process for preparing citrus fibers from a citrus fruit comprising a flavedo, albedo and juice vesicles, comprising the following steps:

(a) subjecting the citrus fruit or a part of the citrus fruit to a homogenization treatment to obtain a homogenized fraction,

(b) contacting the homogenized fraction with an organic solvent to obtain an organic solvent washed citrus fraction, and (c) separating the organic solvent and water from the organic solvent washed citrus fraction to obtain the citrus fiber ,

wherein the citrus fruit is the fruit of the species Citrus aurantium.

The applicants discovered that the citrus fibers prepared from the fruit of the Citrus aurantium species have the property of a high water retention capacity and, sometimes, even higher than that of the citrus fibers prepared under the same conditions from of typical orange citrus fruits. The application of the fruits of the Citrus aurantium species as raw material for the preparation of citrus fibers is also advantageous, because it provides a use for the more than 5 million kilos of fruits of the Citrus aurantium species obtained annually only in Seville, Spain. . Until now, a large volume use for these fruits was not known. The present invention provides such use.

The term "citrus fiber", as used herein, refers to a fibrous pectocellulose product as described, for example, in the aforementioned publications.

The fruit of the species Citrus aurantium is also known as Seville orange, sour orange, bitter orange, Zhi shi, and marmalade orange. Citrus aurantium are native to eastern Africa and tropical parts of Asia, and can now also be found in Mediterranean regions and parts of the United States. No large volume applications are known for these fruits. In small volumes, the fruit of the Citrus aurantium species is used in a variety of applications including food, cosmetics, essential oils for perfumes, and aromatherapy products. It has been used in traditional Chinese medicine for the treatment of nausea, indigestion, and constipation. Bitter orange peel extract has been used in dietary supplements as a fat loss aid and as a suppressant. of appetite. Although citrus fibers have been prepared for many years, it was not known how to prepare citrus fibers from the fruit of the species Citrus aurantium, not to mention that a product with a high water retention capacity could be obtained.

The fruits of Citrus aurantium can be used as is. The fruits can be found in public areas where Citrus aurantium grows. In areas where many of these trees are present, the fruits cause an environmental problem. This is because the fruits are inedible, and therefore there is no desire to collect them. Currently, the fallen fruits are collected and disposed of, usually in landfills or by combustion. The present new use of these fruits solves an environmental problem.

The fruits can be subjected to extraction processes to isolate the cosmetic and pharmaceutical compounds as described above before being used as a material to prepare the citrus fiber. The citrus peel obtained in said processes can be subjected to a process such as, for example, that described in the documents WO12016190 WO2018/119058 and WO2017/023722 mentioned above to prepare the citrus fiber.

Preferably, the citrus fiber is prepared from the rind of the Citrus aurantium fruit. More preferably, part of the citrus fruit comprising at least part or all of the albedo is used. This may be the fruit from which only the juice is extracted or partially extracted. Part of the entire flavedo can be removed as described in US4526794 to obtain the part of the citrus fruit comprising at least part or all of the albedo. The fruit shells can optionally be obtained by pressing the fruits in a screw press, where an emulsion, also known as press liquor, it is separated from the rind. The peel, also known as the press cake, will comprise albedo and have a reduced juice content compared to the initial fruit. Juice reduction can also be achieved by cutting the fruit in half and squeezing part of the juice vesicles from the citrus halves. This can be done using apparatus such as those described in the documents US2020093169, US2021186080, US2020288763 and US2020323252.

Citrus fiber can also be prepared from the juice vesicles present in the juice extracted from the fruit as described above. The juice vesicles can be removed from the juice by filtration or with the use of centrifugal forces, as in a centrifuge, from the juice before it is subjected to the homogenization of step (a).

From the juice separated from the fruits, sugars and/or citric acid can be isolated by well known processes.

The homogenization treatment of step (a) can be effected by a number of possible methods including, but not limited to, high shear treatment, pressure homogenization, colloidal milling, intensive mixing, extrusion, ultrasound treatment, and combinations thereof. Preferably, the homogenization treatment is a pressure homogenization treatment. Pressure homogenizers typically comprise a reciprocating piston or plunger pump together with a homogenizing valve assembly attached to the discharge end of the homogenizer. Suitable high pressure homogenizers include the high pressure homogenizers manufactured by GEA Niro Soavi of Parma, Italy, such as the NS Series, or the Gaulin and Rannie series homogenizers manufactured by APV Corporation of Everett, Massachusetts, USA. For other process conditions, reference is made to the document WO12016190 mentioned above.

Preferably, the peel obtained in the form of press cake or squeezed citrus halves is suitably reduced in size to a size of less than 2 mm, preferably less than 1 mm and more preferably less than 0.5 mm before carrying out the treatment. previous pressure homogenization of step (a). Said size reduction can be carried out by means of a colloid mill, a mechanical crusher or a hammer mill.

In stage (b), the homogenized fraction obtained in stage (a) is brought into contact with an organic solvent to obtain a citric fraction washed with organic solvent, in stage (b), water, flavors are extracted , odors, colors and the like of the homogenized fraction. The solvent should preferably be polar and miscible with water to better facilitate removal of the desired components. Some examples of suitable solvents are lower alcohols such as methanol, ethanol, propanol, isopropanol, butanol, or acetone. The preferred solvents are ethanol, isopropanol, and combinations thereof. The solvent can be provided in an aqueous solution.

Preferably, the homogenized fraction is contacted with the organic solvent at a solids to solvent weight ratio of at least about 0.25:1, preferably at least about 0.5:1, and often from at least about 0.75:1, from about 1:1 to about 5:1, or from about 1.5:1 to about 3:1, based on wet weight of solids. In a realization, the ratio of solids to solvent is approximately 2:1.

Step (b) can be carried out in a single stage, but is preferably carried out by multi-stage extraction, eg a two-, three- or four-stage extraction process, and preferably by counter-current extraction.

In step (c), the organic solvent and water are separated from the organic solvent-washed citrus fraction, yielding the citrus fiber. This can be by means of filtration, centrifugal forces and/or by drying. Preferably, the water and the organic solvent are separated from the citrus fiber by evaporation of the water and the organic solvent using well-known drying processes, such as those described in the aforementioned documents WO12016190, WO2018/119058 and WO2017/023722. previously.

The invention will be illustrated by the following examples.

Example 1

853 grams of peel of the species Citrus aurantium were mixed with 1336 grams of tap water. This mixture was wet ground, first with an immersion blender and then with IKA Ultra-turrax, to a particle size < 0.5 mm. The hull and ground water mixture was homogenized using a GEA Niro Soavi TwinPanda 600 dairy homogenizer, which has 2 plungers and a two-stage homogenization valve. In a first phase, the pressure drop was 36,000 kPa (360 bar) and, in a second phase, the pressure drop was 4,000 kPa (40 bar). 1120 grams of the homogenized fraction were placed in contact with 2010 grams (from 50 to 99 per percent isopropanol) in 3 phases. At higher scales, ie industrial scale, less organic solvent is used per mass of ground shell. The citrus fibers were subsequently dried, obtaining a citrus fiber product with 90 % dry matter.

The water retention capacity of these citrus fibers was measured according to the following procedure. An empty 50 ml tube with cap included was weighed. Approximately 1.0 gram of the obtained dried citrus fiber was added to the tube and the exact weight noted. Tap water was added to a total volume of approximately 50 ml. The shell and water were mixed by shaking. After 10 minutes, the samples were spun in a centrifuge for 10 minutes at 3000 rpm. The supernatant was decanted and the tube with the sediment was weighed. This weight was corrected for tube weight and shell weight, assuming the remainder to be bound water. Water holding capacity was defined as the amount of bound water (in grams) per gram of fiber. The water retention capacity of the citrus fibers of this example 1 was found to be 32 g/g.

comparative experiment A

Example 1 is repeated except that instead of the peel of the species Citrus aurantium, the peel of Citrus sinensis was used. These are the typical fruits used to prepare edible orange juice. The water retention capacity of the citrus fibers obtained was 18 g/g.

Claims (12)

1. Process for preparing citrus fibers from a citrus fruit comprising a flavedo, albedo and juice vesicles, comprising the following steps: (a) subjecting the citrus fruit or a part of the citrus fruit to a homogenization treatment to obtain a homogenized fraction, (b) contacting the homogenized fraction with an organic solvent to obtain an organic solvent washed citrus fraction, and (c) separating the organic solvent and water from the organic solvent washed citrus fraction to obtain the citrus fiber , where the citrus fruit is of the species Oitrus aurantium. 2. Process according to claim 1, wherein part or all of the juice is separated from the fruit, obtaining part of the citrus fruit before subjecting the obtained part of the citrus fruit to step (a). 3. Process according to claim 2, wherein the sugars and/or citric acid are isolated from the juice. 4. Process according to any one of claims 1-3, wherein, in step (a), part of the citrus fruit comprises at least part or all of the albedo. 5. Process according to claim 4, wherein the part of the fruit 1 citric is a citrus peel obtained in an extraction process to isolate cosmetic and/or pharmaceutical compounds from the fruits. 6. Process according to any one of claims 1-4, wherein the part of the citrus fruit is obtained in a screw press in the form of a press cake. 7. Process according to any one of claims 2-4, wherein the part of the citrus fruit is citrus halves from which all or part of the juice is squeezed. 8. Process according to any one of claims 1-7, wherein the homogenization treatment is a pressure homogenization treatment. 9. Process according to claim 8, wherein the pressure homogenization treatment is carried out on particles having a size of less than 0.5 mm. 10. Process according to claim 9, wherein the particles having a size of less than 0.5 mm are obtained by colloidal milling. 11. Process according to any one of claims 1-10, wherein the organic solvent is isopropanol. 12. Use of the fruit of the Citrus aurantium species as raw material to prepare citrus fibers.