FI67774B - FOERFARANDE FOER AROMATISERING AV VATTENLOESLIGA PARTIKLAR AV ROSTAT KAFFE VILKA AER ANVAENDBARA SOM TILLSATS I LOESLIGT POWDER AV ROSTAT KAFFE - Google Patents

Description

ηα fi1, ADVERTISEMENT PUBLICATION (in nna ΪΒ3 (11) UTLÄGGNINGSSKRIFT 6/7/4 • «Sfl c (45) '13' 6 13 ^ {£ -js £ 'Oi rc.„ en to vc jo 1 :: t (51 ) Kv.lk.4 / lnt.CI.4 A 23 F 5/46, A 23 L 1/234 SUOMI FINLAND (2.1) Patent application - Patentansökning 793111 (22) Application date - AnsSkningsdag 08.10.79 (23) Start cloud - Glltlghetsdag 08.1 0.79 (41) Become public - Bllvit offentlig jj .04.80

National Board of Patents and Registration (44) Date of publication and date of publication. - 28 02 85

Patent and Registration Office in the United States of America and Other Publications * * 3 (32) (33) (31) Privilege claimed - Begird piiorltet 10.10.78 USA (US) 950337 Verified-Styrkt (71) General Foods Corporation, 250 North Street, White Plains, New York IO625, USA (72) Stephen Francis Hudak, Croton-on-Hudson, New York, Fouad Zaki Saleeb, Pleasantvi1le, New York, USA (74) Oy Kolster Ab (54) ) Method for flavoring water-soluble particles of roasted coffee used in addition to soluble powder of roasted coffee - Förfarande för aromatisering av vattenlösliga partiklar av rostat kaffe, vilka är användbara som tillsats i lösligt

The invention relates to a method for flavoring water-soluble particles of roasted coffee used in addition to a soluble powder of roasted coffee to provide an upper surface aroma of the package when the powder is enclosed in the package.

Soluble beverage powders, such as spray-dried coffee or tea products, are relatively flavorless compared to their source materials, namely roasted and ground coffee and fermented tea leaves. The same low aroma content occurs in dried fruit juices, such as freeze-dried orange juice, compared to the natural fruit from which the juice is derived. Low aroma content is also present in certain types of roasted coffee ingredients, such as most decaffeinated coffees and concentrated roasted coffee ingredients described in U.S. Pat. 1,903,362, 3,615,667 and 4,261,466. These 2,6774 low-aroma root products initially contain a small amount of flavor, so that the consumer perceives only a slight flocculation when the product package is opened for the first time and quickly fades quickly when the product is first opened. so that during subsequent openings of the package, during the typical period of use of the product, the consumer will notice only a slight aroma or no aroma at all.

It should be noted that the terms "coffee product" and / or "tea product" refer not only to substances consisting of 100% coffee and / or tea, but also to substitute or extended coffees and tea products which may contain roasted grains, chicory and / or other vegetable substances alone or in combination with coffee and / or tea.

Until now, most attempts to add natural flavor to food products have focused on adding the flavor of roasted coffee to soluble coffees, such as shower or freeze-dried coffee. Thus, this invention understandably relates to the field of aromatization of soluble coffee products; however, it has been contemplated that this invention will be used to flavor other food products.

Today, virtually all commercial soluble coffees have been combined with coffee oil, for example, by spraying soluble coffee before packaging with either pure or aroma-enriched coffee oil. In this way, a soluble coffee substance is obtained with an aroma that is more similar to that of roasted and ground decaffeinated coffee. The addition of coffee oil is usually accomplished by a well-known oil coating method (disclosed in U.S. Patent No. 3,148,070) or by an oil spray method (disclosed in U.S. Patent No. 3,769,032).

Coffee oil, with or without added flavorings, has been the preferred medium used to flavor coffee material, as such products can still be considered pure coffee; however, methods developed for the production of coffee oil (see Sivetz, Coffee Processing Technology, Part 2,

Avi Publishing Company, 1963, pages 21-30) such as solvent extraction or separation of coffee oil from roasted coffee are not particularly desirable because manufacturers are left with either solvent-containing roasted coffee or oil-free cake, both of which must either be further processed or discarded. Adding oil to a coffee product has also proven cumbersome in that undesirable oil droplets may appear on the surface of a liquid beverage made from an oil-containing product. Thus, it would be advantageous to develop methods for flavoring coffee products, all of which use coffee or other plant products but do not require the preparation or use of coffee oil or other glyceride material.

A food flavoring method that does not require the use of artificial ingredients or chemical modification of natural ingredients would have uses in the food industry in addition to coffee and tea products. Powdered fruit juices, powdered fruit-flavored beverage concentrates, and jelly dessert mixes are just some of the potential applications. The use of pressurized aromatic oils, such as orange oil and lemon oil, has been tried in the food industry, but their use has been limited by the instability of these oils. If the flavorings contained in these oils or other fruit substances could be kept permanently in the natural plant material, the natural flavorings could be combined into a number of different food products.

The process according to the invention for flavoring water-soluble roots of roasted coffee used in addition to soluble powder of roasted coffee is characterized in that a) roasted coffee is made into dry, water-soluble particles with a microporous structure with a most likely pore radius of about 1.5-15 nm (15-150 Å). ) and having an average particle size of less than 200 by spraying an aqueous solution of roasted coffee into a liquid which is a cryogenic liquid having a temperature below -100 ° C or an anhydrous organic solvent and which removes water from the aqueous solution and forms porous solids from water-soluble solids. particles to form solid particles by separating the particles from the liquid and drying the particles; and b) contacting the microporous particles with volatile aromatic compounds derived from roasted coffee to enclose the aromatic compounds in the pores of the particles in an amount of 0.1-2.0% by weight of the particles.

4,67774

Water-soluble particles of roasted coffee are obtained by drying aqueous solutions of coffee. These particles are made in such a way that the particles have an average diameter (calculated as a weight percentage distribution) of less than 200, preferably less than 150, usually between about 50 and 150, and have a microporous structure containing micropores with a probable radius of less than 15 nm (150 Å), preferably less than n.

11 nm, most preferably less than 5 nm. The most probable beam between 1.0-3.5 nm has been found to be most preferred for this invention. Micropores smaller than n.

1.5 nm, while thought to be desirable for the purpose of this invention, has not been found to be readily achievable and is considered to constitute a practical lower limit for the most probable radius parameter. A pore radius of less than about 0.3 nm is undesirable because such a small size would exclude molecules of aromatic compounds that are desired to be attached to the microporous structure.

The fine pore structure of the porous particles obtained according to the present invention was determined by analyzing the carbon dioxide-gas adsorption-desorption isotherms of these particles obtained at -78 ° C. A standard gas adsorption titration instrument made entirely of glass was used following methods known to those skilled in the art of surface chemistry (Brunauer, S., "The Adsorption of Gases and Vapors," Part 1, Princeton Univ. Press, 1945). Normally, adsorption isotherms are determined by first measuring the amounts of ecu that are adsorbed at different but successively increasing equilibrium pressures and then reducing the pressure to obtain the iso-term desorption branch.

Desorption isotherms are usually the result of ordinary multilayer adsorption and condensation in the pores, in which case the Kelvin equation can be used to estimate the decrease in vapor pressure of the adsorbed substance (CCl 4) due to the concavity of the concave surface of the liquid in the pore. In its simple form and assuming that the surface is completely wetted (contact angle = O), the pore radius (r) is obtained from the formula

r = ~ 2 k V

RT In (P, / P) do 5 67774 where k is the surface tension of the liquid sorbed substance (CC 2), V is the molar volume, is the pressure in the desorption branch of the isotherm and Pq is the saturated vapor pressure (760 mmHg for CC> 2 - 78 ° C: in). The Kelvin equation shows that there is a logarithmic relationship between the pore radius and the relative pressure (P ^ / Pq). Narrower pores are filled at lower relative pressures, wider pores are filled at higher pressures, and the entire pore space is filled at saturation pressure. Additional finenesses must be used in the Kelvin equation to correct for gas adsorption, which adsorption occurs simultaneously with gas condensation (Barrett, E.P., Joyner, L.G., Ρ.Ρ. Halenda, J. Amer. Chem. Soc. 73 (1951) 373). The calculation is then performed to obtain the relative pressures and thus the gas volumes (v) adsorbed corresponding to the selected pore radii (r). Plotting Δν / νΔ r (ml / g) / (nm) in the coordinate system as a function of r (nm) gives the pore volume distribution curves. The shape of these distribution curves reflects the uniformity or dispersion of pores of different sizes in a given sample. As will be appreciated by those skilled in the art, the pore size distribution in a given porous material generally follows a clockwise curve as a distribution pattern, and the term "most probable radius" is intended to refer to a radius corresponding to the peak of the pore volume distribution curve.

Aqueous solutions used to make dry particles are usually obtained by water extraction of roasted coffee.

There are several methods that can be used to make particles with the desired microporous structure. Conventional spray drying gives dry particles that do not have a microporous structure. Conventional freeze-drying gives particles with a probable pore radius well above 1000 nm. The pores are necessary for enclosing volatile aroma compounds, such as those found in the aroma of coffee, for example, in the microporous structure of the dry particle. The retention of flavoring agents by the dry particles of this invention is believed to result from both adsorption and, in particular, capillary condensation (i.e., liquefaction of vapors in the pores). Flavorings are maintained in a microporous structure without the need for any coating on the surface of the particles. However, a small percentage of these flavors are released as a result of the low partial pressure provided by the entrapped flavors. The capillary condensation mechanism does not occur in oversized pores where surface coating of the particles is necessary to retain flavoring agents.

The dry porous particles produced in accordance with this invention are used, after contact with the desired flavors, to impart a top-of-the-box flavor to low-flavor food products enclosed in the package, such as the Porous Coffee Products mentioned above. These particles are combined with the food product in a preferred amount of between 0.1-2.0%, most preferably between about 0.2-1%. Typically, the dry flavored soluble particles of this invention are only mixed with a dry, low aroma, powdered food product.

Dry particles less than 200 μm in diameter and having a pore structure with a most likely pore radius of less than 15 nm. Obtained from aqueous solutions of coffee ingredients by various methods.

An aqueous solution, preferably having a dry matter content of less than 40% by weight, typically 25-35% by weight, is sprayed onto a cryogenic liquid having a temperature below -100 ° C, preferably liquid nitrogen, and the lyophilized portions of the solution are subsequently freeze-dried to give microporous particles with a most likely pore radius of less than 5 nm. The spraying should provide particles with an average particle size of less than 200 microns in diameter so that the entire particle freezes in the blink of an eye upon contact with the cryogenic liquid. It is believed that the blinking of the eye results in the formation of only very small ice crystals throughout the particle. If the sprayed droplets had an average diameter of more than 200 μm, then even at the temperature of liquid nitrogen, the frozen particle has the desired small ice crystals only on its surface and not throughout its entire structure. The agitation of these small ice crystals appears to give the desired microporous structure of this invention. The use of a cryogenic liquid with a temperature above -100 ° C has not been found to give the most likely pore radius below 15 nm, regardless of the diameter of the spray droplets.

Another way to produce dry microporous particles is to spray an aqueous solution into an anhydrous organic solvent, such as 100% ethanol, which both removes water from the extract and forms porous particles from the water-soluble solid 7,77774. Soluble coffee particles prepared in this way have been found to have the most likely pore radius below 5 nm. It is also possible to start from powdered spray-dried particles, such as soluble coffee, and boil these particles in an edible organic solvent such as ethanol, preferably after grinding, to etch the surface of the particles and provide the desired pore structure. Again, it is desirable to produce or use particles having an average diameter of less than 200 microns to provide a sufficient surface area for etching the solvent so that a sufficient number of desired micropores are generated.

The microporous particles produced in accordance with this invention can retain volatile aroma compounds up to about 2% by weight. In actual use, it is difficult to reach levels of more than 1% of flavorings. Retention of flavorings below about 0.1% by weight would require the addition of 5% or more of flavored particles to the soluble food product. It is usually preferred to add aromatized particles in an amount of less than 2% by weight. Preferably, the aromatized particles of this invention contain 0.2% or more of flavoring agents, typically about 0.5%.

The ways in which the porous particles are contacted with flavoring agents to retain flavor within the particles can be many and varied. High pressures and / or low particle temperatures can be used to maximize aroma uptake and reduce the time required to achieve the desired level of aroma; however, such conditions are not required. However, it is desirable to reduce the amount of moisture that comes in contact with the soluble porous particles both before, during and after flavoring. Suitable condensation, evaporation, sweeping and / or separation methods can be used to separate moisture from flavoring agents in flavoring gas streams, flavoring agents or liquid flavoring condensates.

It is also desirable to separate the flavors from the carrier gas (e.g., the CO 2 with which they travel). Methods that can be used to adsorb flavorants to porous substrates include: (1) placing both the porous particles and the condensed CO 2 flavor mist in a well-mixed container with air holes, preferably above -40 ° C, and allowing the CX portion of the mist to be added. 8 67774, (2) enclosing both the adsorbent and the condensed fragrance mist in one or two interconnected pressure vessels and then raising the temperature in the frosted vessel to vaporize the frost and provide an elevated pressure; wetting the particles, (4) condensing the flavoring agents onto the cooled porous particles, (5) feeding a low moisture gas stream containing the flavoring agents through a mattress or column of external particles.

The flavoring agents used for this invention can be derived from many sources well known to those skilled in the art. Depending on the contact method used, the flavoring agents may be present as a component of a gas, as a liquid condensate, or as a condensed frost. Flavoring agents that may be used include coffee oil flavoring agents such as those described in U.S. Pat. 2,947,634, flavorings obtained during the roasting of raw coffee, as described in U.S. Pat.

2,156,212, flavorings obtained during the grinding of roasted coffee, as described in U.S. Pat. 3,021,218, steam-distilled volatile flavors derived from roasted and ground coffee, as described in U.S. Patent Nos. 2,562,206, 3,132,947, 3,244,521, 3,421,901, 3,532,507, and 3,615 665 and vacuum distilled flavorings derived from roasted and ground coffee, as described in U.S. Patent Nos. 2,680,687 and 3,035,922. Of course, it would also be possible to use volatile synthetic chemical compounds that enhance or mimic flavor compounds naturally present. in roasted coffee, fermented tea or other fragrant food products.

Flavors adsorbed to microporous particles in accordance with this invention have been found to be stable during long storage under inert conditions such as are normally found in packaged soluble coffee products. These absorbed flavors are capable of imparting the desired top-of-pack flavor to the packaged products and, if present in sufficient amounts, can also provide the desired taste effects.

67774

Example 1

An aqueous coffee extract having a soluble dry matter content of 33% by weight was prepared by reconstituting solid spray-dried coffee. This extract was sprayed into an open vessel containing liquid nitrogen, after which the extract particles immediately frozen and dispersed. The extract was sprayed with a glass double-liquid disintegration nozzle (chromatographic nozzle manufactured by SGA Scientific, Inc.) using air as the pressure medium. The liquid nitrogen and the mixture of particles were poured into the freeze-drying cells and the liquid nitrogen was allowed to boil to leave a layer of frozen particles about 1.6-3.2 mm thick. The cells were placed in a freeze dryer and placed under a vacuum of 10 μg and a plate temperature of 50 ° C for 18 hours. The freeze dryer vacuum was filled with dry CO 2 and dry particles with a moisture content of less than 1.5% were removed from the freeze dryer and kept away from moisture contact. The dry particles were found to have a microporous structure containing pores with a most likely radius of about 2.4-2.8 nm and the following sieve analysis:

Standard U.S. Sieve Size Weight% _ (mesh) __ (mesh width) at 80 0.177 7.5 at 100 0.149 15.0 200 0.074 67.3 at the base 10.2

The dry particles were then cooled on dry ice in a dry atmosphere and mixed with a gas grinder of a coffee grinder having a moisture content of 10-15% by weight in a weight ratio of 0.2 parts of frost per part of particles. The mixture was transferred to a pre-cooled can with a small air hole and the can was stored at -18 ° C overnight during which time CO 2 evolved. The cooled particles with a moisture content of less than 6% by weight were then packed in glass cans in an uncoated, solid agglomerated spray-dried with coffee in an amount of 0.75% by weight of spray-dried solid. These cans were then stored at 35 ° C for 8 weeks. After the first opening and during the normal 7-day period of use, a pleasant top-level aroma is observed, which was found to be at least as good as the top-level aroma in cans containing, for comparison, aromatized, agglomerated spray-dried coffee coated with coffee grinder. with gas-enriched coffee oil. This coffee oil-coated sample was prepared according to U.S. Patent No. 4,119,736 using a soluble product per unit weight of the amount of refinery gas mist comparable to that used in the example of the invention.

Example 2 100 ml of a coffee extract containing 50% by weight of soluble solid is sprayed with a glass chromatography nozzle into a large beaker containing 3.8 liters of pure ethanol. The ethanol was at room temperature and stirred during spraying. The soluble coffee particles were then filtered from ethanol and these particles were placed in a vacuum oven (635 mmHg vacuum and about 90 ° C) overnight to remove residual ethanol. The obtained particles were found to have a microporous structure with the most probable pore radius of 3.3 nm. The particles were kept out of contact with moisture and contacted with the gas-frost of the coffee grinder in a weight of 2 parts frost per 1 part in a Parr apparatus heated to about 20 ° C. The resulting flavored particles were combined and packaged with uncoated and unflavoured spray-dried coffee agglomerate in an amount of about 0.5% by weight. The can aroma of this sample after 1 week of storage at room temperature was found to be comparable to a week old, gas-enriched oil-coated agglomerate of a coffee grinder.

Example 3

The agglomerated spray-dried coffee was ground and the particles which passed through a sieve with a mesh width of 0.297 mm were separated and 150 g of these particles were added in 2000 to any 100% ethanol. This mixture was boiled for 24 hours in a steam-jacketed vessel with an overhead reflux condenser and a stir bar.

The coffee particles were then filtered from the alcohol and dried in vacuo for 24 hours at 80 ° C and about 630 mmHg. The dried particles weighed a total of about 90 g (about 60 g of solid coffee dissolved by ethanol) and had a pore structure where the most likely pore radius was about 10.2 nm. Two parts (11,677,74 by weight of fox) of these particles were contacted with one part of the coffee grinder gas frost as shown in Example 1, and the resulting flavored particles were packaged with agglomerated spray-dried coffee in an amount of about 0.5% by weight. After one week of storage, the top aroma of the package of this sample was found to be comparable to a week old, gas-enriched, oil-coated agglomerate of the coffee grinder at room temperature.

As mentioned above, the top aroma of the package is provided by commercially soluble coffee products by coating an aromatic glyceride (e.g., coffee oil) on a soluble powder.

It has also been contemplated to absorb coffee flavors into oil-coated soluble coffee, and this method is clearly set forth in U.S. Patent No. 3,823,241. However, it has not previously been thought possible to absorb large amounts of flavors directly into soluble solid coffee to retain flavors. U.S. Patent No. 3,823,241 notes the criticality of the oil so that when the package of soluble coffee is repeatedly opened (i.e., during a period of use), the can aroma is constantly detected by the consumer. Thus, the situation is, in fact, for the conventional spray-dried, foam-dried and freeze-dried products discussed in this U.S. patent. However, this same defect does not occur in porous soluble coffee particles with a most likely pore radius of less than 15 nm. As mentioned above, does conventional spray-dried coffee not have a microporous structure? while in conventional freeze-dried coffee, the most likely pore radius is on the order of 1000 nm.

As can be seen from the following table comparing the rate at which aroma is released from the aromatized particles of the soluble coffee of Examples 1-3 compared to the aromatized particles of spray-dried coffee reduced to a comparable particle size by grinding with carbonic acid, the aromatic release (micrograms) that is erased from the substrate as a function of the sweep time. Carbon values were obtained by sweeping a known amount of weight of coffee (0.5 g) with a stream of nitrogen (30 ml / min.) At 30 ° C for 2000 seconds. The removed volatiles 67774 were recorded every 200 seconds. The table shows the amount (expressed as a percentage of the total) of the flavor released (cumulatively) as a function of the sweep time, taking the flavor released in 2000 seconds as 100%.

Table I

Amount of flavor released (%) Sweeping time (yug carbon / g coffee) (s) _Example 1 Example 2 Example 3 Comparison 200 51 36 55 69 400 74 56 74 87 600 82 67 82 94 800 88 76 87 96 1000 92 82 91 97 1200 94 87 93 98 1400 97 91 96 98 1600 98 94 97 99 1800 99 97 98 99 2000 100 100 100 100

As can be seen from Table 1, the spray-dried reference material, which does not have a microporous structure, releases the aroma most rapidly and thus would not be suitable for imparting the top aroma of the package during use.

Example 4

A series of porous particles were prepared according to the following methods: 1) spray-dried, agglomerated coffee powder was reconstituted to a 33% soluble solid, and this extract was sprayed onto liquid nitrogen using a glass Kro matgoraf nozzle. The resulting frozen particles were lyophilized at 10 ugHg and 25 ° C for 16 hours. Particles that did not pass through a sieve with a mesh width of 0.297 mm were screened out.

2) Same as 1, but the powder was reconstituted to a 50% soluble solid. 3) Spray-dried, agglomerated coffee powder was reconstituted to a 33% soluble solid and sprayed into 100% ethanol. The resulting particles were collected and placed in a vacuum drier at 100 ° C and a vacuum of 13,677,764,635 mmHg for 16 hours. 4) 300 g of spray-dried agglomerate were ground and boiled in 2000 ml of 100% ethanol. The resulting particles were dried at about 90 ° C and 635 mmHg in vacuo for 16 hours. A batch of each of these four samples was flavored by contacting the coffee grinder gas frost in a weight ratio of 0.4 parts frost per part substrate. Contact was achieved by mixing frost and substrate together in a vessel cooled with dry ice. The aroma-containing particles were placed in separate refrigerated cans equipped with air holes and placed in a -18 ° C freezer overnight. Thereafter, 0.2 g of each aromatized sample was placed in a 250 ml glass stoppered flask, and the cubic centimeter of the resulting supernatant aroma contained in the flasks was then evaluated using standard carbon gas chromatographic methods. A portion of all of these flavor-containing particles were also subjected to a pre-identified nitrogen sweep test (2000 seconds at 30 ° C) to assess the amount of flavor substances they contained. This nitrogen sweep test was also performed on unflavoured samples. The results of these two evaluations are presented in Table 2 below.

Table 2 Sample no Porosity Flavor released Free top state (nm) (4 μg carbon / g coffee) (GC calculation in __million) 1 2.3-2.8 28.5 1-flavored "1790 1.375 2 over 14.0 6.75 2- flavored "458 0.304 3 3.3 2.11 3- flavored" 2055 0.847 4 10.0 3.06 4- flavored "723 0.448

Table 2 shows the amount of flavorant that can be absorbed by the porous particles of this invention relative to the amount of flavorant present in the non-flavored particles, as well as the ability of these particles to produce an upper aroma comparable to the upper aroma of the coffee grinder gas-enriched coffee oil produced above. according to said U.S. Patent 4,119,736.

Claims (4)

14 67774 A method for flavoring water-soluble particles of roasted coffee used in addition to soluble powder of roasted coffee to provide a top aroma aroma when the powder is enclosed in a package, characterized in that a) roasted coffee is made into dry, water-soluble particles having a microporous structure , 5-15 nm (15-150 Å), and having an average particle size of less than 200 μm, by spraying an aqueous solution of roasted coffee into a liquid which is a cryogenic liquid having a temperature below -100 ° C or an anhydrous organic solvent and which liquid removing water from the aqueous solution and forming from the water-soluble solids particles having a porous structure to form solid particles by separating the particles from the liquid and drying the particles; and b) contacting the microporous particles with volatile aromatic compounds derived from roasted coffee to enclose the aromatic compounds in the pores of the particles in an amount of 0.1-2.0% by weight of the particles. Process according to Claim 1, characterized in that the microporous particles are contacted with carbon dioxide fumes containing the flavorings of roasted coffee at a temperature above -40 ° C. A method according to claim 1 or 2, characterized in that the coffee particles having a microporous structure are prepared by spraying an aqueous solution of roasted coffee with liquid nitrogen, whereby the droplets of the sprayed coffee solution freeze immediately; separating the frozen particles from the liquid nitrogen; and freeze-dried frozen particles. Process according to Claim 1 or 2, characterized in that the coffee particles having a microporous structure are prepared by spraying an aqueous solution of roasted coffee into an anhydrous organic solvent, preferably 100% ethanol, which removes water from the aqueous solution of roasted coffee and forming soluble particles having a microporous structure. having an average particle size of less than 200 μm; separating the particles from the aqueous solvent, preferably by filtration; and removing the residual solvent, preferably by vacuum drying. 15 Patentkrav S »1 7 4