MXPA00004138A - Starch-protein composition of high firmness and low viscosity gel and procedure thereof - Google Patents

Abstract

It is provided a starch-protein composition of high firmness and low viscosity gel;the starch-protein composition contains a protein material and a starch material forming conjunctly a complex where the starch material is in a substantially not gelatinized state;the starch-protein composition has low viscosity before its coction, but high firmness of gel after being cooked;it is also provided a meat emulsion containing a meat material and the starch-protein composition;it is provided a procedure to form the starch-protein composition in which an aqueous suspension of a protein material is formed, the protein in the suspension is denaturalized when submitting it at enough temperatures to denaturalize the protein, a starch material is mixed in the denaturalized protein suspension, and the starch and protein material suspension is dry by aspersion under conditions which make that the starch material and the protein material form a complex without gelatinizing the starch material;it is provided a procedure to form a meat emulsion with the starch-protein composition in which the meat material and the starch-protein composition are mixed together under insufficient conditions to gelatinize the starch material in the starch-protein composition.

Description

COMPOSITION OF PROTEIN-STARCH OF HIGH FIRMNESS OF GEL AND LOW VISCOSITY, AND PROCEDURE TO PRODUCE BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to a high-viscosity low-gel protein-starch composition, to a meat emulsion containing the same, and to a process for producing the protein-starch composition and meat emulsion. . Very particularly, the present invention relates to a protein-starch composition containing a complex of a protein material and a starch, wherein the starch is substantially in its native non-gelatinized conformation, and to an emulsion of meat containing the same .

DESCRIPTION OF THE RELATED TECHNIQUE Protein materials are widely used to supplement meat products since meat is scarcer worldwide, and much more expensive than protein materials, which are relatively abundant. For example, soy protein materials such as soy isolates and soy concentrates are commonly used as meat analogues or as meat extenders. The protein materials can be used in various forms of meat products, for example, a protein material can be mixed with ground meat to form meat cakes useful for hamburgers, meat pies or other applications of ground meat, or a protein material can mix with meat and stuff into tripe to form frankfurters, sausages or similar products. The protein materials can be combined with plant components to reduce the cost of producing meat emulsions from the protein materials and to provide meat emulsions having improved meat-like characteristics. For example, wheat flour can be co-dried with a vegetable protein material such as soy protein isolate to form a composition useful as a meat extender component in a pet food emulsion that provides gel firmness to the emulsion after of pasteurization. Carbohydrates from plant materials are commonly used with protein materials to provide desirable characteristics to protein materials and meat emulsions containing said protein materials. Starch is a particularly useful carbohydrate for use in combination with protein materials since starch is abundant and can improve the texture and flavor of meat emulsions formed as a complementary protein material. Meat emulsions containing a protein material mixed with starch have improved moisture and fat absorption characteristics, which leads to improved flavor and smoothness after baking the meat emulsion. In a study comparing the moisture retention capacity of soy protein and a filling material formed of cold-mixed soy protein and starch, the filler material was found to have a higher moisture retention capacity, and, therefore, it was determined that it was the preferred material for forming meat emulsions. I. Rogov & V. Dianova, Studv of the Hyqroscopic Properties of Meat and Meat Products, Myasnaya Industriya SSSR, No. 12, pp. 29-31 (1978). Mixtures of protein and starch mixed in dry or cold mixed, while providing desirable moisture characteristics and fat absorption in a meat emulsion, provide a relatively weak gel firmness and emulsion stability to a meat emulsion even after the emulsion is cooked. Gel firmness and emulsion stability are desirable in a meat emulsion so that the meat emulsion has a firm meat-like texture with a stable protein and moisture level. A starch-protein complex having improved gel firmness and emulsion stability is described in the U.S.A. No. 4,159,982 to Hermansson. The starch-protein complex is formed by heating starch with an aqueous dispersion of casein at a temperature above the gelation temperature of the starch. The casein protein forms a complex with gelatinized starch granules. The degree of gel firmness of the complex is greater than that of the casein itself, and the emulsion stability of the protein is improved. The gelatinization of the starch in the presence of proteins to form a protein-starch complex, while improving the gel firmness and emulsion stability of the protein, excessively increases the viscosity of the complex in relation to a dry mixture of the protein and starch, as well as that of a meat emulsion material containing the complex in relation to a meat emulsion containing a mixture of protein and starch made dry or cold. The processing of the high viscosity protein-starch complex into a meat emulsion, and the processing of the resulting high viscosity meat emulsion material is difficult and expensive on a commercial scale, since high viscosity materials do not flow easily . Therefore, what is required is a process for forming a low viscosity protein-starch composition and a meat emulsion containing it, which have a high gel firmness and emulsion stability after being cooked.

BRIEF DESCRIPTION OF THE INVENTION The present invention is a protein-starch composition which has a low viscosity in water and is capable of forming a firm gel after cooking. The protein-starch composition contains a protein material and a starch material. The protein material and the starch material are complexed, however, the starch material is in a substantially non-gelatinized state. In one embodiment of the invention, at least a portion of the starch material of the protein-starch composition is partially encapsulated in the protein material. In another aspect, the invention is a meat emulsion containing a protein-starch composition and a meat material that are mixed together. The protein-starch composition is formed from a protein material and a starch material, wherein the protein material and the starch material are complexed, and the starch material is in a substantially non-gelatinized state. In still another aspect, the invention is a process for forming a low viscosity protein-starch composition having a high gel firmness and emulsion stability after being cooked. An aqueous suspension of a protein material is formed. The suspension of protein material is treated at a temperature and for a time effective to denature the protein material. A non-gelatinized starch material is then added to the suspension of denatured protein material at a suspension temperature below the gelatinization temperature of the starch material. The suspension of denatured protein material and starch material is spray dried under conditions sufficient to substantially couple the protein material and the starch material, but insufficient to substantially gelatinize the starch material to form the protein-starch composition . In another aspect, the present invention is a process for forming a low viscosity meat emulsion that maintains a high gel firmness and emulsion stability after cooking. A protein-starch composition containing a starch material coupled to a protein material is provided, the starch material being substantially in its native non-gelatinized conformation. An aqueous suspension of the protein-starch composition is formed, and the suspension is mixed with a meat material to form a meat emulsion. The protein-starch composition of the present invention has a very low viscosity suitable for use in the large-scale commercial production of meat emulsions, and has a gel firmness and emulsion stability comparable to that of a starch-protein complex. gelatinized once the composition is cooked. Prior to cooking the protein-starch composition of the invention, or a meat emulsion containing the composition, the starch of the protein-starch composition is coupled to the protein substantially in its native state and not gelatinized. This substantially reduces the viscosity of the protein-starch composition in relation to a complex of gelatinized starch-protein, since the gelatinized starch is much more viscous than the non-gelatinized starch. After cooking the protein-starch composition or a meat emulsion containing the protein-starch composition, the closely associated protein and starch are more complexed while the starch is gelatinized by the cooking temperature, thereby developing a high firmness of gel and emulsion stability in relation to a mixture of protein and starch made in dry or cold.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a photograph of the protein-starch composition of the present invention, illustrating the non-gelatinized starch material encapsulated in the protein material.

DESCRIPTION OF THE PREFERRED MODALITIES As used herein, gelatinized starch is defined as starch that has become hydrated and swollen relative to its native state as a result of being treated at a temperature, pressure or mechanical shear sufficient to alter the structure of the native starch. . Gelatinized starch is much more viscous in water than native ungelatinized starch, since the gelatinized and swollen starch granules interact frictionally and because some of the swollen starch granules break up releasing amylose, which binds easily to hydrogen to form a gel. The non-gelatinized starch, as used herein, is defined as a starch in its native state that has not been gelatinized. The protein material used in the process of the present invention to form the protein-starch composition must be capable of forming an emulsion with a meat material such as minced meat or minced meat, when the protein material and the meat material combine together in an aqueous mixture. Therefore, the protein material should not be excessively soluble in water under conditions of neutral pH. Preferably, the proteins in the protein material have an average associated molecular weight of more than 30,000 daltons, most preferably more than 100,000 daltons and more preferably between about 100,000 and 360,000 daltons, to ensure that the protein material is not excessively soluble in water under neutral pH conditions. The protein material used in the process of the present invention to form the protein-starch composition can be an animal protein material or a vegetable protein material. In one embodiment of the invention casein can be used as the protein material. Casein is prepared by the coagulation of a skim milk cream. Casein is coagulated by acid coagulation, natural souring or rennet coagulation. To carry out the coagulation with casein acid, a suitable acid, preferably hydrochloric acid, is added to the milk to lower the pH of the milk to approximately the isoelectric point of the casein, preferably at a pH of about 4 to about 5, and most preferably at a pH of about 4.6 to about 4.8. To carry out the coagulation by natural souring, the milk is kept in tanks to ferment, causing the formation of lactic acid. The milk is fermented for a period of time sufficient to allow the lactic acid formed to coagulate a substantial portion of the casein in the milk. To carry out the coagulation of the casein with rennet, sufficient rennet is added to the milk to precipitate a substantial portion of the casein in the milk. Caseins coagulated with acid, naturally sourced and precipitated with rennet are all commercially available from various manufacturers or supply houses. Preferably, the protein material is a plant protein material because the vegetable protein materials are cheap, abundant and well adapted to form a starch-protein composition. Isolate of soy protein, soy concentrate or soybean meal are the vegetable protein materials that are preferred and used in the process for forming the protein-starch composition, although the protein-starch composition can also be formed from other sources of vegetable and animal protein such as peas, wheat and rapeseed. Soybean meal, as the term is used herein, refers to a pulverized form of a defatted soy material, preferably containing less than 1% oil, formed of particles having a size such that the particles can pass through. through a No. 100 mesh screen (United States standard). The soy material can be pastel, small fragments, flakes, flour or a mixture of these materials, which are pulverized to create a soybean meal using conventional soybean grinding procedures. The soybean meal has a soy protein content of about 40% to about 60%. Soy concentrate, as the term is used herein, refers to a soy protein material containing about 60% to about 80% soy protein. The soy concentrate is preferably formed from a commercially available defatted soy flake material from which the oil has been removed by solvent extraction. The soy concentrate is produced by washing the soy flake material with an aqueous solvent having a pH around the isoelectric point of the soy protein, preferably at a pH of about 4 to about 5, and most preferably at a pH of approximately 4.4 to approximately 4.6. The isoelectric wash removes a large amount of water-soluble carbohydrates and other water-soluble flake components, but removes very little protein, thereby forming a soy concentrate that dries after the isoelectric wash. Soy protein isolate, as the term is used herein, refers to a soy protein material having a protein kinase of about 80% or more, preferably a protein content of about 90% or more , and most preferably about 95% or more of protein content. In one embodiment of the invention that is most preferred, the protein material used in the method of the invention is a soy protein isolate because of the high protein content of the soy protein isolate. The soy protein isolate is preferably formed from a commercially available defatted soy flake material from which the oil has been removed by solvent extraction. The soy flake material is extracted with an aqueous alkaline solution, typically a solution of calcium hydroxide or sodium hydroxide having a pH of about 6 to about 10, to form an extract containing protein and water-soluble components of the Soy flake is separated from insoluble cellulosic fibers and materials from flakes. The extract is then treated with an acid to lower the pH of the extract to approximately the isoelectric point of the protein, preferably at a pH of about 4 to about 5, and most preferably at a pH of about 4.4 to about 4.6, precipitating from this. way the protein. The protein is then separated from the extract and dried using conventional separation and drying media to form the soy protein isolate. The protein material can be a modified protein material, wherein the protein material is modified by known methods to improve the suitability of the protein material for use in a meat emulsion. For example, a protein material that is preferred is a modified soy protein isolate having improved whiteness, such as that described in the U.S.A. No. 4,309,344, which is incorporated herein by reference. The enhanced-whiteness modified soy protein isolate is prepared by heating an aqueous solution of precipitated soy protein isolate, present in about 20 to about 30% by weight of the solution, at a temperature of about 46 ° C to about 62.7 °. C for about 1 to about 300 seconds, followed by the concentration of the precipitated protein to a solids level of more than about 44%. Isolates of soy protein and modified soy protein isolates useful in the process of the invention are commercially available. The commercially available soy protein isolates that can be used in the invention include "Supro 500E7 which is a modified soy protein isolate., and "Supro 5157, both of which are available from Protein Technologies International, Checkerboard Square, St. Louis, Mo. The following will describe the process for forming the protein-starch composition of the present invention with respect to a protein isolate. However, other protein materials can be used in a similar way.An aqueous suspension of the soy protein isolate is formed.The aqueous suspension preferably contains about 2% to about 30% soy protein isolate. weight, and most preferably contains about 15% to about 20% of the soy protein isolate by weight.The soy protein isolate is mixed carefully in the suspension for a sufficient period of time to mix the suspension, stirring or mixing the suspension with any conventional means for agitation or mixing able to mix the protein suspension. In one embodiment, the suspension is mixed for about 15 minutes to about 1 hour, and more preferably for about 30 minutes to about 45 minutes at room temperature. The suspension of soy protein material is treated to denature the protein material. The protein material is denatured to unfold it, so that the protein-starch complex can be formed, and to improve the gel and emulsion that form the properties of the protein material. The protein material can be thermally denatured by being treated at a temperature for a sufficient time to denature the soy protein material. For example, the protein material can be denatured by treating the suspension at a temperature of about 75 ° C to about 160 ° C for a period of about 2 seconds to about 2 hours. The preferred method for denaturing the soy protein material is to treat the suspension of protein material at an elevated temperature higher than room temperature, by injecting pressurized steam into the suspension for a sufficient time to substantially denature the protein material, defined in the consecutive as "jet cooking". Jet firing of suspensions of protein material to denature the protein material is well known and conventional in the art. The following description is a preferred method of jet cooking a suspension of soy protein material; however, the invention is not limited to the method described, and includes any known method for jet firing protein suspensions. A suspension of protein material is introduced into the feed tank of the jet oven, wherein the soy protein material is kept in suspension with a mixer which agitates the suspension. The suspension of protein material is directed from the feed tank to a pump which forces the suspension through a reactor tube. Steam is injected into the suspension of soy protein material under pressure as the suspension enters the reactor tube, instantly heating the suspension to the desired temperature. The temperature is controlled by adjusting the pressure of the injected steam, and is preferably from about 85 ° C to about 155 ° C, more preferably about 150 ° C. The suspension is treated at the elevated temperature for about 5 seconds to about 15 seconds, being treated for longer at lower temperatures, and the treatment time being controlled by the flow rate of the suspension through the reactor tube. Preferably, the flow rate is about 503.3 kg / h, and the cooking time is about 9 seconds. After being heated to denature the protein material in the suspension, the suspension is cooled to a temperature below the gelatinization temperature of the starch with which the protein material will be combined. The cooling can be carried out by conventional methods such as allowing the suspension to stand at room temperature until the suspension has cooled, cooling the suspension, or placing it in an ice bath. In a preferred embodiment, after being jet-fired, the suspension of protein material is discharged from the reactor tube of the jet oven into a chamber subjected to vacuum to instantly cool the suspension. The pressure of the suspension is instantaneously reduced to the pressure in the chamber subjected to vacuum, which is preferably from about 25 to about 30 mm Hg. The decrease in pressure instantly cools the suspension to a temperature of about 30 ° C to about 60 ° C, and to about 55 ° C when the suspension is treated at a temperature of about 150 ° C in the jet cooking process. After the suspension of soy protein material is denatured and cooled, a starch material is combined and mixed with the suspension of protein material. It is important that the starch material be added to the suspension of protein material only after the temperature of the suspension of protein material is lower than the gelatinization temperature of the starch material, so that the starch material is not subjected to temperatures which would prematurely gelatinize the starch. Preferably, the starch material is added to the suspension of protein material when the temperature of the protein material suspension is from about 25 ° C to about 45 ° C. The starch material used to form the protein-starch composition is a naturally occurring starch. The starch material can be isolated from a variety of plants such as corn, wheat, potato, rice, maranta and cassava by conventional well-known methods. The starch materials useful in forming the protein-starch composition include the following commercially available starches: corn, wheat, potato, rice, high amylose corn, waxy corn, maranta and tapioca. Although the starches vary in molecular structure, the starches have similar general functional properties, in particular, the ability to couple with a protein material after being spray-dried with the protein material., and the ability to gelatinize after being exposed to temperatures, pressures, or shear stress sufficient to induce gelatinization. Preferably, the starch material used to form the protein-starch composition is a corn starch or a wheat starch, and more preferably it is a toothed corn starch. A preferred toothed corn starch is commercially available from A. E. Staley Mfg., Co., marketed as toothed corn starch, type IV, pearlized. It is preferred that the starch material is not modified. Modified starches are defined herein as native starches which have been chemically or otherwise treated to form a starch derivative. Modified starches often have altered properties such as decreased gelation resistance or elevated gelation temperatures, which are not convenient in the protein-starch composition of the invention. Although modified starches are generally not preferred for use herein, modified starches may be used provided that the modification does not adversely affect the formation of the protein-starch composition and its viscosity, or the emulsion stability and stability properties. of gelation of a cooked emulsion of meat containing the protein-starch composition. The amount of starch material added to the suspension of protein material is selected to provide the desired ratio of protein material: starch material. The ratio of protein material: starch material in the suspension is a factor in the gel firmness of the protein-starch composition formed from the suspension. Higher starch levels may increase the gel firmness of the protein-starch composition. In a preferred embodiment, the starch is added to the suspension of protein material, so that the ratio of protein material: starch material in the suspension by dry weight is from about 45:60 to about 80:20, and more preferably from about 50:50 to about 70:30. The starch material can be added to the suspension of dried protein material, or an aqueous suspension of the starch material can then be formed and added to the suspension of protein material. Preferably, an aqueous suspension of the starch material is formed. The starch suspension preferably contains from about 20% to about 40% by weight of the starch material, more preferably from about 30% to about 35% by weight of the starch material. If a suspension of the starch material is formed, the temperature of the suspension of the starch material should be kept below the gelation temperature of the starch material, which is typically from about 50 ° C to about 70 ° C, to avoid that the starch material gelatinizes. Preferably, the starch material is added to cold water and the suspension is maintained at room temperature. The starch material is mixed in the suspension of the starch material for a sufficient time to thoroughly mix the starch material in the suspension by any conventional means for stirring or mixing the suspension. The gentle agitation should be continued after the suspension is mixed, to prevent the starch material from settling. Care should be taken to mix and agitate the suspension of the starch material not to subject the starch material to excessive mechanical shear stress, so that the starch material is not gelatinized. Other materials may be added to the protein material and suspension of the combined starch material to add desired characteristics to the protein-starch composition formed from the suspension. For example, gums such as guar gum or other compounds such as trisodium phosphate, sodium tripolyphosphate or sodium acid pyrophosphate can be added., to modify the flow characteristics of the protein-starch composition. The suspension containing the protein material and the starch material can be mixed by any conventional means to mix or stir suspensions containing significant amounts of suspended solids. Preferably, the protein material and the starch material are mixed in a stirred tank. The suspension must be thoroughly mixed until it is a homogeneous mixture of the protein material and the starch material. Water can be added to the combined suspensions to adjust the level of suspended solids in the combined suspensions to a level which can be easily manipulated in a spray drying operation. Preferably, the level of suspended solids in the combined suspensions is from about 5% to about 25% by weight, and more preferably is from about 14% to about 17% by weight. The combined suspension of starch material and protein material is then spray dried to form the protein-starch composition. The suspension is spray dried under conditions which cause the protein material and the starch material to be coupled together and form a complex, wherein the starch material remains substantially in its native ungelatinized state. As shown in Figure 1, part of the starch material is at least partially encapsulated in protein when the protein material and the starch material are spray-dried as a whole. Preferably, most of the starch material is encapsulated in the protein material, and more preferably, substantially all of the starch material is encapsulated in the protein material. Spray drying conditions should be moderate to avoid gelatinization of the starch, so that the resulting protein-starch composition has a low viscosity when rehydrated. Preferably, the spray dryer is a co-current flow dryer, wherein the hot inlet air and the protein-starch suspension, atomized upon being injected into the dryer under pressure through an atomizer, pass through. of the dryer in a co-current flow. The protein-starch composition formed by spray drying the suspension in a co-current flow dryer is not subjected to heat degradation or starch gelatinization, since the evaporation of the starch water and the protein materials cool the materials as they dry. In a preferred embodiment, the protein suspension and the starch materials are injected into the dryer through a nozzle atomizer. Although a nozzle atomizer is preferred, other spray dryer atomizers, such as a rotary atomizer, may be used. The suspension is injected into the dryer under sufficient pressure to atomize the suspension. Preferably, the suspension is atomized under a pressure of about 210.9 kg / cm2 to about 281.2 kg / cm2, and more preferably about 246 kg / cm2. Hot air is injected into the dryer through a localized hot air inlet, so that hot air entering the dryer flows co-current with the atomized protein-starch mixture sprayed from the atomizer. The hot air has a temperature of about 287.7 ° C to about 315.5 ° C, and preferably has a temperature of about 290.5 ° C to about 298.8 ° C. The protein-starch composition is collected from the spray dryer. Conventional means and methods of collecting spray-dried materials can be used to collect the protein-starch composition, including cyclones, bag filters, electrostatic precipitators and gravity collection.

The collected protein-starch composition can be used to form a meat emulsion containing the protein-starch composition and a meat material. An aqueous mixture of the protein-starch composition and a meat material is formed, and the protein-starch composition and the meat material are ground or minced together according to conventional methods to combine the protein and meat materials to form the meat emulsion. The meat material may be a meat useful for forming sausages, sausages or other meat products formed by filling a case with a meat material, or it may be a meat such as pork, chicken or beef useful in ground beef applications such as like hamburgers, meatloaf and ground beef products. Particularly useful meat materials include mechanically deboned meat from chicken, beef and pork, pork trimmings, beef trimmings and pork backbone. The ratio of meat material and protein-starch composition in the suspension is selected to provide a meat emulsion having meat-like characteristics. Preferably, the protein-starch composition provides from about 10% to about 20% of the total protein in the meat emulsion, more preferably from about 10% to about 15%, and comprises from about 2% to about 7% of the emulsion of meat, including water, by weight. Preferably, the meat material comprises from about 40% to about 60% of the meat emulsion by weight, and the water comprises from about 30% to about 40% of the meat emulsion by weight. The suspension of the protein-starch composition and the meat material is carefully mixed to form the meat emulsion. The suspension is mixed by stirring or mixing the suspension for a sufficient period to form a homogenous meat emulsion. Excessive shear and temperature above the gelation temperature of the starch in the protein-starch composition should be avoided while mixing the suspension so that the starch in the protein-starch composition does not gelatinize. Conventional means for stirring or mixing the suspension can be used to carry out the mixing. Preferred means for mixing the meat emulsion are a cutter bowl that minces the materials in the suspension with a knife, and a mixer / emulsifier that crushes the materials in the suspension. A preferred cutter bowl is the Hobart Food Cutter Model No. 84142 with an arrow speed of 1725 rpm. After the suspension has been mixed to form a meat emulsion containing the protein-starch composition, the meat emulsion can be used to form meat products. The meat emulsion can be used to fill meat casings to form sausages, sausages and similar products. Meat emulsions can also be used to form ground meat products such as hamburgers, meatloaf and other ground beef products. A meat emulsion containing the protein-starch composition is relatively low in viscosity since the aqueous mixtures containing the protein-starch composition are not particularly viscous. An aqueous suspension of a protein-starch composition containing about 10% to about 20% of the composition, wherein the starch in the protein-starch composition is a corn starch, can have a Brookfield viscosity of about 500 centipoises at about 11,000 centipoise at about 25 ° C, and about 80 centipoise at about 6,000 centipoise at about 60 ° C. An aqueous suspension of a protein-starch composition containing from about 10% to about 20% of the composition, wherein the starch in the protein-starch composition is a wheat starch, may have a Brookfield viscosity of from about 200 centipoise to about 4000 centipoise at about 25 ° C, and from about 50 centipoise to about 700 centipoise at about 60 ° C. A meat emulsion formed from the protein-starch composition and a meat material also has a relatively high gel firmness after being cooked, which gives the cooked emulsion of meat a desirable firm texture.

The present invention is illustrated in more detail by means of the following examples which use a soy protein isolate as a protein material. The examples are designed to be illustrative, and in no way should they be construed as limiting or otherwise limiting the scope of the invention.

EXAMPLE 1 A protein-starch composition is formed according to the process of the present invention with a corn starch. 22.4 kg of the soy protein isolate "SUPRO 500E" from Protein Technologies International, Inc., are made in suspension in 124 kg of water at 21 ° C to form a suspension of protein material having a total solids content of 14.5% . 73 kg of the suspension is treated at 140.5 ° C ± -15 ° C for 9 seconds ± 1 second under pressure to denature the protein, and then the suspension is instantly cooled by being expelled in a chamber subjected to vacuum having a vacuum of approximately 25 mm Hg. A suspension of starch is formed by adding 9,080 kg of toothed corn starch, type IV, obtained from A.E. Staley Mfg. Co. to 14.07 kilograms of cold water. The suspension is stirred in a stirred tank until the suspension becomes homogeneous.

About 18.16 kilograms of the denatured protein suspension and about 5.90 kg of the corn starch suspension are mixed together until the protein and starch suspensions are homogenized. The protein-starch suspension is spray-dried in a co-current type spray dryer at a spray pressure of 3500 psig through a 30SDX nozzle, a maximum 54.4 ° C feed temperature, and an exhaust temperature of air of 93.3 ° C. A spray-dried starch-protein composition formed according to the process of the present invention having a protein: starch ratio of about 55:45 is collected from the spray dryer.

EXAMPLE 2 A meat emulsion is produced to form Frankfurter sausages which contains a protein-starch composition formed in accordance with the present invention. A protein-starch composition is formed similarly to the protein-starch composition of Example 1, but having a protein: starch ratio of about 52:48. Beef trimmings, pork horn, pork trimmings, water, modified food starch, a small amount of oils, seasonings and preservatives, and the protein-starch composition are placed in a chopping bowl. The components are presented in the following percentages, by weight: composition of protein-starch 2%, cuts of beef 22.9%, pig trimmings 21%, pork ridge 5%, water 36.4%, modified food starch 7%, oils and seasonings 5.7%. The mixture is minced into the bowl to mince enough to form a meat emulsion. The meat emulsion is stuffed into suitable casings to form frankfurters, and the stuffed casings are cooked to prepare the frankfurter sausages.

EXAMPLE 3 A protein-starch composition is formed according to the present invention with a wheat starch. 39.95 kg of soy protein isolate "SUPRO 500E" from Protein Technologies International, Inc. are suspended in 221.5 kg of water at 21.1 ° C to form a suspension of protein material having a total solids content of about 14.5% . The suspension is subjected to treatment at 151.6 ° C ± -15 ° C for 9 seconds ± 1 second and under pressure to denature the protein, and then the suspension is cooled instantaneously by introducing it into a vacuum chamber that has a vacuum around of 25 Hg. A suspension of wheat starch is formed by adding 26.78 kg of wheat starch in cold water to form a starch suspension of about 32% total solids. The starch suspension is mixed until it becomes homogeneous.

About 19.97 kg of the denatured protein suspension is added to the starch suspension and the combined suspension is mixed until the protein and the starch are mixed homogeneously in the suspension. The protein-starch suspension is spray-dried in a co-current type spray dryer at a spray pressure of 3500 psig through a 30SDX nozzle, at a maximum supply temperature of 54.4 ° C, and at an exhaust temperature of 93.3 ° C maximum. A spray-dried starch protein composition that is formed in accordance with the present invention is collected from the spray dryer.

EXAMPLE 4 The viscosity of the protein-starch compositions formed in Examples 1 and 3 is measured. The viscosity of each composition is measured in aqueous suspensions at 10%, 12.5%, 15% and 20% of the composition at ° C and at 60 ° C using a Brookfield LVT viscometer. The results are established in table 1.

TABLE 1 Viscosity (cps) Sample Suspension Suspension Suspension Suspension at 10% at 12.5% at 15% at 20% Starch of 547 877 2517 10716 protein-corn 25 ° C Starch of 80 218 522 5733 protein-corn 60 ° C 204 498 450 3716 Starch of 53 123 230 670 protein-wheat 25 ° C Starch of protein-wheat 60 ° C EXAMPLE 5 The gel firmness of the protein-starch compositions formed in Example 1 and in Example 3 is measured. Each composition is mixed with water in a ratio of 1 part of the composition to 6 parts of water, by weight, to a total weight of 2,700 grams. The gel strength of each composition with salt or without added salt is measured after cooking under pasteurization conditions and under retort conditions. The measured gel firmness is established in the following table 2.

TABLE 2 Firmness of gel (g) Sample Pasteurized, Pasteurized, Retorted, Retorted, without salt with salt without salt with salt Starch 877 1021 289 976 protein-corn Starch 715 1191 465 1276 protein-wheat EXAMPLE 6 A comparison of the viscosity and gel firmness of the protein-starch compositions having different protein: starch ratios is made, wherein the protein-starch compositions are formed in accordance with the present invention. An aqueous suspension of soy protein isolate is formed by adding 59.92 kg of "Supro 500E" isolated from soy protein from Protein Technologies International, Inc. to 319.6 kg of water, the water having a temperature of about 29.4 ° C. The protein suspension is mixed uniformly for 45 minutes and then subjected to treatment at a temperature of about 151.6 ° C for about 9 seconds under pressure to denature the protein. The suspension is cooled instantaneously to a temperature of about 54.4 ° C and the suspension is placed in a vacuum chamber having a pressure of about 26 mm Hg.

To compare the effect of the various protein: starch ratios on the viscosity and gel firmness of the protein-starch compositions formed according to the present invention, the cooked protein suspension is divided into three parts ("I", " II "," III ") wherein the protein-starch compositions of reduced protein: starch ratios of 75:25, 70:30 and 42:58 are formed from the l-lll parts of the protein suspension, respectively. Part I is formed by separating 68.1 kg of protein suspension, adding 3.26 kg of toothed corn starch, and mixing the resulting protein-starch suspension for 20 minutes. Part II is formed by separating 56.75 kg of the protein suspension, adding a suspension of toothed corn starch formed from 5.72 kg of toothed corn starch and 11.80 kg of water to the protein suspension, and mixing the protein-starch suspension resulting for 20 minutes. Part III is formed by separating about 45.4 kg of the protein suspension, adding a suspension of toothed corn starch formed of 8.80 kg of starch and 27.24 kg of water to the protein suspension, and mixing the resulting protein-starch suspension for about 20 minutes. The l-lll suspensions are spray-dried separately in a co-current type spray dryer. Each suspension is fed through a spray nozzle at a pressure of about 3500 psig and sprayed into the spray dryer. The drying air that blows through the air inlet of the spray dryer is set at a temperature of about 287.7 ° C, which is sufficient to cause the protein and starch in the l-lll suspensions to interact to form the l-lll protein-starch compositions without causing substantial gelatinization of the starch. Each of the suspensions I-III is dried in the spray dryer at a moisture content of about 5%. About 2.27 kg to about 4.54 kg of the spray-dried material is recovered from each suspension. The viscosity and gel firmness characteristics are determined for the l-III starch-protein compositions. To determine the viscosity of the l-lll protein compositions, a 10% aqueous solution is formed and the viscosity of each is measured using a Brookfield viscometer at around 25 ° C. The results of the viscosity and gel firmness measurements for the l-III protein compositions are set out in the following Table 3.

TABLE 3 Test Sample I Sample II Sample lll 75:25 70:30 42:58 protein / starch protein / starch protein / starch Viscosity 900 580 160 (centipoise) Firmness of gel- 640 760 880 Pastronization Instron, without salt (grams) Firmness of gel- 880 930 1960 Pasteurization Instron, without salt (grams) EXAMPLE 7 A comparison of the relative viscosities of a corn starch protein composition made according to the present invention and a corn starch protein composition containing substantially gelatinized starch is made. A non-gelatinized protein-starch composition according to the present invention is formed as described above in Example 1. Another protein-starch composition is formed in substantially similar manner, except that the starch suspension is mixed with the suspension of the starch. Protein material before treating the suspension of protein material at 140.5 ° C ± -15 ° C for 9 seconds ± 1 second under pressure so that the starch will gelatinize and form a complex with the protein during heating. Aqueous solutions are formed at 10%, 12.5% and 15% of the non-gelatinized protein-starch composition and the gelatinized protein-starch composition. The Brookfield viscosity of each solution is determined at 25 ° C and 60 ° C. The results are established in table 4 following.

TABLE 4 Viscosity (cps) Sample solution at 10% solution at 12.5% solution at 15% Not gelatinized (25 ° C) 547 877 2517 Gelatinized (25 ° C) 650 2175 10100 Not gelatinized (60 ° C) 80 218 522 Gelatinized (60 ° C) 1900 6350 17700 The starch-protein composition of the present invention is substantially less viscous than a gelatinized protein-starch complex. The less viscous protein-starch composition is handled more easily during processing than the viscous gelatinized material.

EXAMPLE 8 A comparison of the relative gel firmness of a wheat protein-starch composition made according to the present invention and a dry mixture of a wheat protein-starch is made. A protein-starch composition made according to the present invention is formed as described in Example 3 above (composition of protein-starch), wherein the resulting product contains 56% protein, by weight, on a dry basis. A dry blend of soy protein isolate and wheat starch is made by dry mixing an isolate of soy protein and wheat starch (dry mix), wherein the resulting product contains 57.6% protein, by weight, on a dry The gel firmness of the protein-starch composition and the dry mixture are measured. The result is established in the following table 5.

TABLE 5 Firmness of qel Sample Pasteurized, Unpasteurized, Retorted, without Retorted, salt with salt salt with salt Protein- 715 1192 465 1276 Starch Dry blend 403 965 0- (not measurable) 838 The protein-starch composition of the present invention has a higher gel firmness than a dry blend of a protein material and a starch after baking for all measured types of cooking. The protein-starch material, therefore, can provide a firmer texture to a meat emulsion after cooking as compared to a dry mixture of protein and starch.

EXAMPLE 9 A comparison of the viscosity and gel firmness of a soy protein isolate, co-dried wheat flour and soy protein composition, and a co-dried wheat starch and soy protein material formed in accordance with the present invention. 38.13 kilograms of soy protein isolate "SUPRO 500E" from Protein Technologies International, Inc. are suspended in 223.36 kg of water at 21.1 ° C to form a suspension of protein material having a total solids content of about 14.4% . The suspension is subjected to treatment at 137.7 ° C for 9 seconds under pressure to denature the protein, and then the suspension is cooled instantaneously by placing it in a vacuum chamber having a vacuum of about 26 Hg. An aqueous suspension of wheat starch containing 30.7% wheat starch is formed by adding 6.12 kg of wheat starch to 19.97 kg of water and uniformly mixing the wheat starch in the water. A separate aqueous suspension of wheat flour containing 31.9% wheat flour is also formed by adding 6.53 kg of wheat flour to 20.47 kg of water and mixing uniformly. The denatured soy protein suspension is divided into three portions, one of which is mixed with the suspension of aqueous wheat starch, another is mixed with the suspension of aqueous wheat flour, and the last one is maintained only with the isolate of denatured soy protein. 63.56 kilograms of the denatured soy protein isolate containing 9.53 kg of isolated soy protein solids are mixed with the wheat starch suspension, and 57.20 kg of the denatured soy protein isolate suspension containing 8.62 kg of isolated solids of soy protein are mixed with the wheat flour suspension. The wheat starch / soy protein isolate suspension, the wheat flour suspension / soy protein isolate, and the remaining denatured soy protein isolate suspension are spray-dried in a co-type spray dryer. current. Each suspension is spray dried at a spray pressure of 3500 psig at feed temperatures of 45.5 ° C to 51.6 ° C, at inlet temperatures of 261.6 ° C to 266.1 ° C, and at a maximum exhaust temperature of 93.3 ° C . 13.62 kilograms of the co-dried wheat starch / protein material, 12.25 kg of the co-dried wheat flour / protein material, and 3.40 kg of the spray dried soy protein isolate are collected. The viscosity of the wheat / protein starch material, the wheat flour / protein material, and the isolated samples of soy protein are compared at 25 ° C and 60 ° C with 10% aqueous suspensions, 12.5%, 15% and 20% of the resive samples using a Brookfield LVT viscometer. The results are established in table 6.

TABLE 6 Viscosity (cps) As can be seen by comparing the viscosities of the samples, the co-dried wheat protein / starch material consistently provides low viscosity, and is less viscous than the co-dried wheat protein / protein material, particularly in higher solid suspensions. Both the co-dried wheat starch / protein and the co-dried wheat / protein meal materials are considerably less viscous than the suspensions of the spray dried protein material. The gel strengths of the wheat starch / co-bound protein material, the jointly dry wheat / protein meal material and the dry protein material are also compared. Each sample is mixed with water in a ratio of one part of the material shows 6 parts of water, by weight, to a total of 270 grams. The gel strength of each sample that has salt added, and that which has no added salt is measured when cooked under pasteurization conditions and under retort conditions. The measured gel strengths are presented in table 7.

TABLE 7 Firmness of gel (q) Sample Wheat Flour Only Wheat Protein / Protein Wheat / Protein Patented Without Salt 1192 772 972 Added 715 442 567 In retort Without salt 1277 829 1055 Added 465 454 460 As can be seen by comparing the gel strengths of the sample, the jointly dry wheat starch / protein material gave better gel firmness when baked under all conditions than the co-dried wheat flour / protein material and the material of dry spray protein. The gel firmness provided by the co-dried wheat / protein starch material is significantly greater than the gel firmness of the other sample under most cooking conditions. In the previous examples, the viscosity of each of the above protein / starch compositions is measured using a Brookfield LVT viscometer (available from Brookfield Engineering Laboratories Inc., Stoughton, Mass.). The gel strengths in the above examples were measured in the following manner. A gel is initially formed of a composition by mixing the dry composition with water in a ratio of 1: 6, preferably to a total weight of 2700 grams, then the resulting mixture is uniformly minced for about 10 minutes in a chopping bowl, preferably a Hobart food cutter model number 84142 with an arrow speed of 1725 rpm. Salt can be added to the gel after approximately 5 minutes of chopping, if the gel firmness to be measured is the gel firmness with added salt. Approximately 28 grams of salt are added per 1400 grams of gel. The gel is then placed in a can, preferably a 307 mm x 113 mm three-cut aluminum can, filled into a can and then the can is sealed. The resulting canned gel is cooked when subjected to pasteurization or retort. To pasteurize a gel, the gel can is placed in boiling water for about 30 minutes. Then the can is removed and cooled for 30 minutes under cold tap water, and then refrigerated for 16 to 24 hours. After cooling, a can of pasteurized or retorted gel is placed in a water bath at 25 ° C-30 ° C for approximately 2-3 hours to achieve thermal equilibrium. The gel is prepared for gel firmness measurement by removing the gel from the can allowing the gel to settle on the bottom of the can. The gel firmness is measured with an Instron Universal Testing Instrument test instrument, model number 1122 with a 36 mm probe. The probe is propelled towards each gel until the gel breaks, which is marked by a maximum on a recorder. The amount of force required to break the gel is determined from the distance that the probe is driven into the gel before the gel breaks. The gel firmness is determined from the force required to break the gel according to the following formula: gel firmness (grams) = (F / 100) (G) (454), where F = fracture point of gel in outline units; 100 = total number of scheme units: G = full scale load in kilograms to a full scale load reading of "x 10", and 454 = number of grams per kilogram. The gel fracture point in diagram units (F) is determined by drawing a tangent to the upper portion of the peak on the diagram, and parallel to the slope. Those skilled in the art will appreciate that various changes can be made to the invention as described without departing from the spirit of the invention. The invention should not be limited to the described embodiments, which are for purposes of illustration, but rather should be limited by the scope of the appended claims and their equivalents.

Claims (50)

NOVELTY OF THE INVENTION CLAIMS

1. - A protein-starch composition containing a low viscosity in water and capable of forming a firm gel under cooking, comprising: a protein material and a starch material, wherein the protein material and the starch material form the complex and said starch material is in a substantially non-gelatinized state.

2. The protein-starch composition according to claim 1, further characterized in that at least some of said starch material is partially encapsulated in said protein material.

3.-. The protein-starch composition according to claim 1, further characterized in that at least a major part of the starch material is encapsulated in the protein material.

4. The protein-starch composition according to claim 1, further characterized in that substantially all the starch material is encapsulated in the protein material.

5. The protein-starch composition according to claim 1, further characterized in that a material selected from 1 or more of guar gum, trisodium phosphate, sodium tripolyphosphate and sodium acid pyrophosphate.

6. - The protein-starch composition according to claim 1, further characterized in that said protein material is present in said composition in a ratio of protein material to starch material of from about 45:65 to about 80:20 by weight dry.

7. The protein-starch composition according to claim 6, further characterized in that said protein material is present in said composition in a ratio of protein material to starch material of about 50:50 to about 70:30. in dry weight.

8. The protein-starch composition according to claim 1, further characterized in that said starch is selected from one or more of a group comprising corn starch, potato starch, wheat starch, rice starch, maranta, tapioca starch and mixtures thereof.

9. The protein-starch composition according to claim 8, further characterized in that said starch is corn starch.

10. The protein-starch composition according to claim 8, further characterized in that said starch is wheat starch.

11. - The protein-starch composition according to claim 1, further characterized in that said protein material is not excessively soluble in water under conditions of neutral pH.

12. The protein-starch composition according to claim 11, further characterized in that the protein in said protein material has an average associated molecular weight greater than 30,000 daltons.

13. The protein-starch composition according to claim 12, further characterized in that the protein in said protein material has an average associated molecular weight greater than 100,000.

14. The protein-starch composition according to claim 13, further characterized in that the protein in said protein material has an average associated molecular weight greater than 100,000 and approximately 360,000 daltons.

15. - The protein-starch composition according to claim 1, further characterized in that said protein material is selected from one or more of an animal protein, a vegetable protein and mixtures thereof.

16. The protein-starch composition according to claim 15, further characterized in that said material of protein material is casein.

17. The protein-starch composition according to claim 15, further characterized in that said protein material is a vegetable protein material derived from one or more of chicharros, wheat or rapeseed.

18. The protein-starch composition according to claim 15, further characterized in that said protein material is a soy protein material.

19. The protein-starch composition according to claim 18, further characterized in that said soy protein material is selected from at least one of a soy protein isolate, a soy protein concentrate or a soybean meal. soy.

20. A meat emulsion comprising: a protein-starch composition formed of a protein material and a starch material, wherein said protein material and said starch material complex and said starch material is in a state substantially not gelatinized; and a meat material that is mixed with said protein-starch composition.

21.- The emulsion of meat in accordance with the claim 20, further characterized in that at least some of said starch material in the protein-starch composition is at least partially encapsulated in the protein material.

22. The emulsion of meat in accordance with the claim 21, further characterized in that at least a major part of said starch material in the protein-starch composition is encapsulated in the protein material.

23. - The meat emulsion according to claim 20, further characterized in that said protein-starch composition contains a material selected from one or more of guar gum, trisodium phosphate, sodium tripolyphosphate and sodium acid pyrophosphate.

24.- The emulsion of meat in accordance with the claim 20, further characterized in that said protein material is present in said protein-starch composition in a ratio of protein material to starch material from about 45:65 to about 80:20 dry weight.

25.- The emulsion of meat in accordance with the claim 20, further characterized in that said starch of the protein-starch composition is selected from one or more of a group comprising corn starch, potato starch, wheat starch, rice starch, maranta, tapioca starch and mixtures thereof. same.

26.- The emulsion of meat in accordance with the claim 20, further characterized in that said protein material of the protein-starch composition is not excessively soluble in water at neutral pH conditions.

27. The meat emulsion according to claim 20, further characterized in that said protein material of the protein-starch composition is selected from at least one of caffeine, soy protein material or plant protein material derived from pea, wheat or rapeseed.

28. - The meat emulsion according to claim 27, further characterized in that said protein material of the protein-starch composition is a soy protein isolate or a soy protein concentrate.

29.- The emulsion of meat in accordance with the claim 20, further characterized in that said meat material is selected from at least one mechanically deboned chicken, mechanically deboned beef, mechanically deboned pork, pork meat trimmings, beef trimmings or pig backbone.

30.- The emulsion of meat in accordance with the claim 20, further characterized in that the protein-starch composition comprises from about 2% to about 7% of said meat emulsion by weight.

31. The meat emulsion according to claim 20, further characterized in that said protein-starch composition provides from about 10% to about 20% of the total protein in said meat emulsion.

32. The meat emulsion according to claim 20, further characterized in that said meat material comprises from about 40% to about 60% of said meat emulsion by weight.

33.- A process for forming a protein-starch composition, comprising: forming an aqueous suspension of a protein material; treating said suspension at a temperature and for an effective time to denature said protein material; adding a non-gelatinized starch material to said suspension of denatured protein material at a suspension temperature at a low gelatinization temperature of said starch material; and spray-drying the suspension of denatured protein material and the starch material under conditions sufficient to form a complex of substantially said protein material and said starch material but insufficient to substantially gelatinize the starch material.

34. The method set forth in claim 33, further characterized in that said suspension of protein material is formed to contain from about 2% to about 30% by weight of said protein.

35.- The procedure set forth in claim 33, further characterized in that said protein material is caffeine or a soy protein material.

36.- The method set forth in claim 33, further characterized in that said suspension is treated at a temperature of about 85 ° C to about 155 ° C for a period of about 5 seconds to about 15 seconds to denature said protein material .

37.- The method set forth in claim 33, further characterized in that said suspension is treated at a temperature of at least about 121 ° C for a period of at least 5 seconds to denature said protein material.

38.- The method set forth in claim 33, further characterized in that said non-gelatinized starch material added to the suspension of denatured protein material is an aqueous suspension of a non-gelatinized starch containing from about 20% to about 40% by weight. weight of said ungelatinized starch material.

39.- The method according to claim 33, further characterized in that said starch material is added to the suspension so that the protein material and the starch material are present in said suspension in a ratio of protein material to material of starch from about 45:65 to about 80:20 in dry weight.

40.- The method according to claim 39, further characterized in that said starch material is added to the suspension so that the protein material and the starch material are present in said suspension in a ratio of protein material to material of starch from about 50:50 to about 70:30 in dry weight.

41.- The process according to claim 33, further characterized in that said starch is selected from a group consisting of corn starch, potato starch, wheat starch, rice starch, maranta, tapioca starch and mixtures thereof .

42.- A process for forming a low viscosity meat emulsion that achieves a high gel firmness and high emulsion stability when cooked, comprising: providing a protein-starch composition containing a starch material complexed with a material of protein, said starch material being in its native non-gelatinized conformation; forming an aqueous mixture containing the protein-starch composition and a meat material; and combining said mixture of the protein-starch composition and meat material under insufficient conditions to gelatinize the starch material in the protein-starch composition to form a meat emulsion.

43.- The method according to claim 42, further characterized in that said protein material in the protein-starch composition is caffeine or a vegetable protein material.

44. The method according to claim 43, further characterized in that said plant protein material is a soy protein material.

45. The process according to claim 42, further characterized in that said starch material in the protein-starch composition is selected from the group comprising corn starch, potato starch, rice starch, wheat starch, maranta, tapioca starch and mixtures thereof.

46. - The method according to claim 42, further characterized in that said protein material and said starch material of the protein-starch composition are present in the protein-starch composition in a ratio of protein material to starch material of around 45:65 to about 80:20 in dry weight.

47.- The method according to claim 46, further characterized in that said protein material and said starch material of the protein-starch composition are present in the protein-starch composition in a ratio of protein material to protein material. starch from about 50:50 to about 70:30 in dry weight.

48. The method according to claim 42, further characterized in that said aqueous mixture of the protein-starch composition and meat material contain from about 2% to about 7% by weight of the protein-starch composition. 49.- The method according to claim 42, further characterized in that the meat material is a ground meat or a raw meat. 50.- The method according to claim 42, further characterized in that it consists of stuffing a casing with said meat emulsion.