Soluble Protein Compositions And Methods Of Their Making

Abstract

This disclosure provides a high quality soluble protein composition and the processes of making the same. The compositions are shelf-stable, easy to use and have excellent nutritional values as compared to other protein products. The compositions may be prepared from animal sources, such as chickens or turkeys.

Claims

1. A method for making a soluble protein composition from a starting material derived from an animal source, said composition comprising one or more soluble proteins, said method comprising: (a) incubating said starting material with an enzyme at a temperature between about 120° F. and 140° F. for a time period between 1 and 3 hours, (b) heating the mixture from step (a) to at least 180° F. for at least five minutes to fully cook the mixture and denature the enzymes and form a cooked slurry, (c) incubating the cooked slurry of step (b) further at a temperature between about 200° F. and 300° F. under a pressure between 10 and 15 psig for a time period between 1 and 6 hours to form a fully cooked slurry, (d) separating the fully cooked slurry of step (c) into at least a fat layer, a broth layer and a meaty layer, and (e) collecting said broth layer to obtain said soluble protein composition.

2. The method of claim 1, wherein said separation step (d) is carried out by centrifugation.

3. The method of claim 1, wherein said enzyme in step (a) comprises a protease.

4. The method of claim 3, wherein said protease has a working concentration in the range of 0.01%-1% by weight.

5. The method of claim 3, wherein said protease has a working concentration of about 0.2% by weight.

6. A method for making a first protein composition and a second protein composition from a starting material derived from an animal source, said first protein composition being soluble, and said second protein composition being insoluble, said method comprising: (a) incubating said starting material with an enzyme at a temperature between about 100° F. and 160° F. for a time period between 0.1 and 12 hours, (b) heating the mixture from step (a) to at least 180° F. for at least five minutes to fully cook the mixture and denature the enzymes and form a cooked slurry, (c) incubating the cooked slurry of step (b) further at a temperature between about 200° F. and 300° F. for a time period between 0.1 and 12 hours to form a fully cooked slurry, (d) separating the fully cooked slurry of step (c) into at least a solid fraction and a liquid fraction, and (e) collecting said liquid fraction to obtain said first protein composition, and collecting said solid fraction to obtain said second protein composition.

7. The method of claim 6, wherein said liquid fraction comprises a fat layer and a broth layer, said broth layer being collected as said first protein composition.

8. The method of claim 6, wherein said incubating in step (c) is performed under a pressure between 10 and 15 psig.

9. The method of claim 1, further comprising an acidification step (f) to reduce the pH of said soluble protein composition obtained from step (e).

10. The method of claim 9, wherein said acidification step (f) comprises adding an acidic agent to said broth layer obtained from step (e) or partially hydrolyzing said broth layer, wherein said acidic agent is selected from the group consisting of carbonated water, carbon dioxide gas, and combination thereof.

11. The method of claim 1, further comprising a microfiltration step (g), said microfiltration selectively enriching certain proteins or certain amino acids in said composition obtained from step (e).

12. A method of making a food or beverage product, comprising the step of using the soluble protein composition obtained in claim 1 as an ingredient of the food or beverage product.

13. The method of claim 12, wherein said food or beverage product is selected from the group consisting of protein drink, smoothies, and other nutritional beverages.

14. A method of making a dietary supplement, comprising the step of using the soluble protein composition obtained in claim 1 as an ingredient of the dietary supplement.

15. The method of claim 14, wherein said dietary supplement is a prebiotic supplement.

Description

DETAILED DESCRIPTION

[0022] This disclosure relates to a process for making a complete, high quality soluble protein composition from an animal source, such as poultry (e.g., chicken or turkey). In one aspect, the proteins in the disclosed compositions are soluble in water. The disclosed composition may be used by food processors and consumers in a convenient form, for example, as a shelf-stable powder. In another aspect, the amino acid profile offered by this composition is well balanced and obtains excellent scores for PDCAAS.

[0023] In one embodiment, the disclosure provides methods of making a high quality protein composition from chicken. Chicken is widely consumed in numerous applications as a healthy, nutritious food. Chicken broth is also widely used as the foundation for many classic foods including soups, stews, chowders, gravies, and sauces. More recently, chicken broth has been used widely in meal kits such as stir fry. However, chicken broth has historically scored lower than insoluble meat proteins in feeding studies, with lower digestibility and PER scores. The PER or Protein Efficiency Ratio score may be derived from growth weight of an animal fed a measured weight of food containing that protein as the only protein in the ration.

[0024] As compared to other broth products, the disclosed compositions provide a better balance of amino acids and are a better source of proteins than regular broth prepared according to conventional methods.

[0025] Based on Protein Efficiency Ratio testing results, the soluble protein composition disclosed herein is comparable to the highest quality proteins such as egg, and in many cases even exceeds the scores of whey and soy proteins.

[0026] Table 1 shows the abundance of amino acids in one exemplary soluble protein composition. Weight percentages of amino acids in the composition are shown in Solids.

TABLE-US-00001 TABLE 1 Amino acid profile of the disclosed composition on Solids basis Disclosed composition % of AA Aspartic Acid (w/w) 8.45 Threonine (w/w) 4.14 Serine (w/w) 3.90 Glutamic Acid (w/w) 15.97 Glycine (w/w) 6.00 Alanine (w/w) 5.93 Valine (w/w) 4.10 Methionine (w/w) 2.38 Isoleucine (w/w) 4.03 Leucine (w/w) 7.24 Tyrosine (w/w) 2.79 Phenylalanine (w/w) 6.17 Histidine (w/w) 2.59 Lysine (w/w) 8.03 Arginine (w/w) 6.38 Proline (w/w) 4.69 Hydroxyproline (w/w) 1.62 Cysteine (w/w) 0.41 Tryptophan (w/w) 0.83 Total 95.66

[0027] In another aspect, the amino acid profile of the disclosed soluble protein composition is well balanced. Table 2 shows amino acid profiles of one exemplary soluble protein composition prepared according to the present disclosure. In a study to evaluate the quality of proteins based on amino acid requirements by humans and on protein digestibility, the disclosed protein composition is shown to have a high score (for example, 90) for Protein Digestibility Corrected Amino Acid Score (“PDCAAS”).

TABLE-US-00002 TABLE 2 Amino acid profile of the disclosed composition Disclosed Commercial composition broth % of % of AA total AA total Aspartic Acid (w/w) 8.83 6.88 Threonine (w/w) 4.33 2.39 Serine (w/w) 4.07 3.06 Glutamic Acid (w/w) 16.69 14.96 Glycine (w/w) 6.27 17.28 Alanine (w/w) 6.20 8.35 Valine (w/w) 4.29 2.84 Methionine (w/w) 2.49 1.47 Isoleucine (w/w) 4.22 2.10 Leucine (w/w) 7.57 4.56 Tyrosine (w/w) 2.92 1.27 Phenylalanine (w/w) 6.45 2.03 Histidine (w/w) 2.70 2.17 Lysine (w/w) 8.40 4.73 Arginine (w/w) 6.67 7.05 Proline (w/w) 4.90 10.49 Hydroxyproline (w/w) 1.69 7.76 Cysteine (w/w) 0.43 0.43 Tryptophan (w/w) 0.87 0.20 100.00 100

[0028] Table 3 shows the typical amino acid composition in total chicken meat protein (USDA SR-21 released Dec. 7, 2011 by U.S. Department of Agriculture).

TABLE-US-00003 TABLE 3 Typical amino acid composition of meat protein from chickens Weight (mg) Aspartic Acid 3870 Threonine 1834 Serine (w/w) 1494 Glutamic Acid 6504 Glycine 2133 Alanine 2369 Valine 2155 Methionine 1203 Isoleucine 2293 Leucine 3259 Tyrosine 1466 Phenylalanine 1724 Histidine 1348 Lysine 3689 Arginine 2619 Proline 1785 Hydroxyproline ND Cysteine 556 Tryptophan 507 Total 43400

[0029] Table 4 shows the content of metals and minerals in one exemplary soluble protein composition prepared according to the present disclosure.

TABLE-US-00004 TABLE 4 Metal and Mineral content of the disclosed composition from chickens Amount Aluminum <10 ppm Calcium  0.03% Chromium <1.2 ppm Copper 1 ppm Iron 0.0011% Magnesium 0.0824% Manganese <0.5 ppm Nickel <0.7 ppm Phosphorus  0.71% Potassium  1.58% Selenium 0.72 ppm Sodium  0.64% Zinc 14 ppm

[0030] In one embodiment, the disclosed soluble composition contains significantly higher concentration of tryptophan (greater than 0.6% of total amino acids) as compared to commercially available broth (about 0.1-0.3%). See Table 2. The use of enzyme in the present process may help render more tryptophan-containing proteins (or peptides) soluble. In another aspect, the amount of hydroxyproline is relatively low (e.g., 1.69% in one embodiment) in one broth composition as compared to commercially available broth (e.g., 7.76%).

[0031] In another embodiment, because the disclosed soluble protein compositions provide complete amino acid profile in a single high quality soluble protein source, there is no need to mix multiple protein sources or to supplement any particular amino acids. Indeed, as shown by Protein Efficiency Ratio (PER) testing, the soluble protein compositions of the present disclosure are comparable to the highest quality proteins such as those from eggs, while in many cases, exceeding the scores of whey, pea and soy proteins. Protein efficiency ratio (PER) is measured based on the weight gain of a test subject divided by its intake of a particular food protein during the test period.

[0032] Due to conditions such as kidney disease, some people must monitor their dietary protein intake closely. For these people, proteins of the highest quality are optimum for sourcing and consumption. In one embodiment, the soluble proteins of the disclosed composition may be easier for kidneys to process than regular digested proteins.

[0033] In one aspect, the disclosed process may be used to turn lower value raw poultry materials into a high value protein powder or broth without using additives. By way of example, several representative steps of one of the embodiments of the disclosed processes are described below:

[0034] 1. In one embodiment, raw chicken muscle such as boneless meat or trims may be used as the starting material. Alternatively, raw chicken frames and carcasses may be converted to mechanically separated chicken using equipment and techniques available in the art.

[0035] 2. This material may be finely ground to allow optimum fractionation of protein from fat and other non-protein materials. Pieces of the starting raw material may be ground to less than 5 mm, 4 mm, 3 mm, 2 mm, or less than 1 mm size.

[0036] 3. The finely ground chicken starting material may be mixed with water as needed for easy handling.

[0037] 4. Protease enzyme(s) may be added to the mixture at an optimum percentage that depends on the enzymes used and the finished product desired. This mixture is heated to an optimum digesting temperature and allowed to react for an optimum time. Process times and temperatures are varied for best results. By way of example, a weight of enzyme equal to 0.2% of the protein content of the raw material may be used, and the temperature may be set at 130° F. for two hours.

[0038] 5. After the enzyme treatment, the mixture is heated to at least 180° F. for at least five minutes to fully cook the mixture and denature the enzymes. This initial cooking time and temperature may also be varied to achieve desired results.

[0039] 6. The cooked slurry may be further cooked to optimize the amount of product yielded and optimize the amino acid profile of the finished product. The product may be cooked at very high temperatures and pressures for an extended time if needed. Parameters for this additional cooking may include, for example, at a temperature between 230 and 300° F. for a time period between 1 and 6 hours.

[0040] 7. After all cooking is completed, the desired soluble protein fraction (broth) is separated from the fat and solids fractions and collected for further processing. It may be collected by various techniques known in the art, which include but are not limited to screening, decanting, settling, and filtering.

[0041] 8. The collected soluble protein broth may be concentrated for use or sale in liquid versions or dried by methods known in the art to make a powder.

[0042] The processing step combination of enzyme digestion and extended cooking of the finely ground product results in a high yield of soluble protein that has shown by amino acid analysis to be of higher quality than regular broth products made simply by plain cooking, regardless of the materials or cooking process used. The combination of enzymatic and thermal processes extract and provide more essential amino acids than those extracted using existing processes.

[0043] In one embodiment, the soluble protein compositions may be used as an ingredient in food or beverage products. In another embodiment, the composition obtained may be used in numerous applications as a wholesome, all natural ingredient. The disclosed extract may also be used to prepare protein drinks, smoothies, or other nutritional beverages.

[0044] It is to be noted that, as used in this specification and the claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a device” may include reference to one device, as well as two or more devices, unless the context clearly limits the reference to one device.

[0045] The terms “between” and “at least” as used herein are inclusive. For example, a range of “between 5 and 10” means any amount equal to or greater than 5 but equal to or smaller than 10.

[0046] Unless otherwise specified, the percentage of certain component in a composition is by weight of total solid. Various commercially available products may have been described or used in this disclosure. It is to be recognized that these products are cited for purpose of illustration only. Certain physical and/or chemical properties and composition of the products may be modified without departing from the spirit of the present disclosure. One of ordinary skill in the art may appreciate that under certain circumstances, it may be more desirable or more convenient to alter the physical and/or chemical characteristics or composition of one or more of these products in order to achieve the same or similar objectives as taught by this disclosure.

EXAMPLES

[0047] The following examples are provided to illustrate the present invention, but are not intended to be limiting. The reagents, materials and instruments are presented as typical components, and various substitutions or modifications may be made in view of the foregoing disclosure by one of skills in the art without departing from the principle and spirit of the present invention.

Example 1 Preparation of a Soluble Protein Composition From Poultry Using One or More Enzymes

[0048] Raw mechanically separated chicken (MSC) was placed into a vessel with an equal amount of water. Two protease enzymes were added at 0.2 percent (by weight) of chicken solids and thoroughly mixed into the raw slurry. The mixture was heated to 130° F. (or about 54.4° C.) and held for 2 hours with intermittent agitation. The mixture was then put into a pressure vessel (or cooker) and cooked at 10-15 psi (240 to 250° F.) for 3 hours. This step helped fully cook the product and completely denatured the enzymes. The cooked slurry was allowed to cool to less than 200° F. for safe handling. Then, the slurry was centrifuged at 3,500 rpm to separate the slurry into fat, broth, and meaty layers. These different layers were separated and collected. The broth layer was concentrated by evaporation to obtain the soluble protein composition.

[0049] This soluble protein composition was subject to amino acid analysis. The amino acid profile of this composition was compared to those of other chicken broths, which contained only chicken broth with no seasonings, flavorings, or other protein sources. An PDCAAS calculator was used to calculate the PDCAAS (http://www.unjury.com/protein_tools/pdcaas.html). The soluble protein composition of this Example had a PDCAAS of 100 against egg white as the standard. All other control broths scored less than 60.

[0050] A scaled up experiment using the same starting materials and same process was also conducted. The resultant composition after drying contained about 5% moisture, 86.6% protein, 1% fat, and 5.5 ash.

[0051] These results show that the combination of enzyme treatment plus pressure cooking extracted a composition having high quality protein and low fat. The composition also has superior ratio of amino acids.

[0052] The nutritional scores of the disclosed composition (SPC for soluble protein composition) were also compared to a number of other proteins. Various protein compositions were fed to rats and the efficiency of these different protein compositions was measured according to standard protocols. The results of protein efficiency ratio (PER), relative PER (RPER), net protein ratio (NPR) and relative NPR (RNPR) values are shown in Table 6.

TABLE-US-00005 TABLE 6 Comparison of protein quality scores RPER Limiting PER casein Digestibility NPR RNPR PDCAAS DIASS AA Casein 1.93 100 98.21 1.13 100 SPC 1.57 90.53 96.97 1.13 92.77 100 91.10 Leucine Whey 1.19 61.78 97.71 0.45 38.01 100 61.40 Histidine Soy 1.85 95.97 97.63 1.28 104.10 100 46.4 Methionine Pea 0.98 50.81 97.83 0.23 16.33 80.42 36 Methionine

Example 2 Comparison of Soluble Protein Compositions From Poultry Prepared With or Without Using Enzyme

[0053] A control experiment was conducted using the same MSC as starting material under the same protocol but without the use of enzymes. The soluble protein composition obtained under this no-enzyme process had a PDCAAS score between 41 and 57 by using the same PDCAAS calculator. All other control broths scored less than 60.

REFERENCES

[0054] All references listed below and those publications, patents, patent applications cited throughout this disclosure are hereby incorporated expressly into this disclosure as if fully reproduced herein. [0055] Shah et al., U.S. patent application No. 10/912,560. [0056] Shah et al., U.S. patent application No. 10/919,518. [0057] Shah et al., U.S. patent application No. 10/932,295. [0058] Shah et al., U.S. patent application No. 10/972,089. [0059] Shah et al., U.S. patent application No. 11/11/153,435. [0060] USDA SR-21 released Dec. 7, 2011 by U.S. Department of Agriculture.