Process for controlling protein to salt ratio in animal muscle protein composition and protein composition

Abstract

A low salt protein solution not capable of forming a gel is obtained from animal muscle tissue by forming an aqueous acidic protein solution which is filtered to remove salt and acid. The low salt protein solution can be formed into a gel by adding a physiologically acceptable salt to the low salt protein solution and heating the resultant protein solution with added salt.

Description

REFERENCE TO RELATED APPLICATION [0001] This application is a continuation-in-part application of application Ser. No. 10 / 655,604, filed Sep. 5, 2003 which, in turn, is based on provisional application Ser. No. 60 / 464,614, filed Apr. 23, 2003.BACKGROUND OF THE INVENTION [0002] This invention relates to a process for making an edible functional animal muscle protein concentrate composition and to a process for making the composition wherein gelation of the composition is controlled. More particularly, this invention relates to a process for making the functional animal muscle protein concentrate from animal muscle tissue wherein gelation of the composition is controlled so that its gelation is effected when it is used such as by being added to a food. [0003] Prior to the present invention, protein compositions derived from animal muscle tissue have been available for human consumption as disclosed in U.S. Pat. Nos. 6,005,073; 6,288,216 and 6,451,975 as well as U.S. patent application...

AI Technical Summary

Benefits of technology

[0007] In accordance with this invention, a concentrated protein solution derived from animal muscle tissue is provided which is in the form of an “aqueous acidic protein solution” as defined below. In accordance with this invention, a process is provided whereby a concentrated aqueous acidic protein solution is isolated while controlling the protein concentration in the solution as well as the weight ratio of protein to salt concentration in the solution so that premature gelation of the solution is avoided. Premature gelation is avoided when the weight ratio of protein to salt in the aqueous acidic protein solution is above about 35 and the protein concentration is above about 1.9 weight percent. The weight ratio of protein to salt can be controlled either by adding protein or removing salt from the aqueous acidic protein solution. In one embodiment of this invention, an aqueous acidic protein solution is filtered to produce a retentate. The retentate is referred to herein as the “low salt protein solution” since salt dissolved in aqueous solution comprises the permeate that is separated from the_retentate. The low salt protein solution does not form a gel when heated to a temperature of 55° C. or lower. In contrast, the aqueous acidic protein solution quickly forms a gel when heated to about 35° C. and forms a gel over time within a temperature range of about 4-30° C. or higher. In a second embodiment of this invention, protein derived from animal muscle_tissue is added to the aqueous acidic protein solution to obtain the desired minimum protein concentration and the desired weight ratio of protein to salt whereby the resultant “low salt protein solution” does not form a gel at 55° C. or lower. When salt is added subsequently to the low salt protein solution up to physiological salt concentration (0.86 weight % salt), the resultant solution referred to herein as the “protein solution with added salt” is capable of forming a gel at room temperature or higher, e.g., 30-40° C. Gelation of the protein solution with added salt can be effected at room temperature or with heating whenever gelation is accelerated by heating it. This process for controlling gelation of the protein containing solution permits pasteurizing by heating the protein solution while avoiding gelation. Thus, because the protein solution has been pasteurized, it need not be subsequently pasteurized after it has been added to a food. This control of protein gelation permits addition of the protein to foods which need not be cooked to improve the nutritional value of the food. In addition, direct safe ingestion of the protein is permitted.

[0012] The protein solution with added salt can be injected into a food such as fish or meat or it can be applied to the surface of the food or it can be mixed with the food. The food containing the protein solution with added salt then can be cooked at elevated temperature in the absence of a solid moisture barrier while retaining a substantial majority of its original moisture. The difference in weight between meat and fish treated in accordance with this invention compared with fish or meat not injected, mixed or coated with the protein solution with added salt is between about 4 and about 21%, more usually, between about 4 and about 10%. Also, in accordance with this invention, it has been found that the addition of the protein solution with added salt to food such as fish or meat provides a preservative effect in that it reduces microbial degradation of the fish or meat. The protein solution with added salt also can be utilized to restrict absorption by food of oil and / or fat used to cook the food. The protein solution with added salt can be applied to the surface of the food or it can be mixed with the food. The food containing the protein then can be cooked in liquid oil and / or fat at elevated temperature while minimizing absorption of oil and / or fat by the food. The difference in weight between food treated in accordance with this invention after being cooked in oil and / or fat compared with food not mixed or coated with the protein after being cooked in oil and / or fat is between about 10 and about 60%, more preferably between about 30 and about 60%. In addition, since the amount of absorbed fat or oil utilized during cooking is substantially reduced, the amount of oil or fat needed to cook a given weight of food is correspondingly substantially reduced.

Problems solved by technology

Unfortunately, the liquid form of these compositions form gels at a time after they are initially formed which is temperature-dependant.

Gel formation of these compositions causes processing problems in that the gel clogs the processing equipment to the point that the composition can not be moved through the processing equipment.

In addition, since gel formation is quicker at elevated composition temperature, the composition cannot be pasteurized with heat while maintaining the composition as a liquid.

This result is undesirable since oftentimes the composition requires pasteurization prior to consumption by humans.

This solution is undesirable since the surface of the meat or fish remains soft rather than having a desirable crust.