Proteins comminution

From animal tissue, especially bovine lung and liver (e. g. autolysis of comminuted tissue parts, heating with ammonium sulfate in alkaline solution, filtration and acidification yield heparin as complex with protein, removal of fat with alcohol and treatment with trypsine for the purpose of decomposition of proteins, precipitation with alcohol and various purification methods). 

Textured Soy Proteins. Textured vegetable proteins, primarily textured flours and concentrates (50% protein and 70% protein, dry basis, respectfully) are widely used in the processed meat industry to provide meat-like structure and reduce ingredient costs (3-6, 9-10). Available in a variety of sizes, shapes, colored or uncolored, flavored or unflavored, fortified or unfortified, textured soy proteins can resemble any basic meat ingredient. Beef, pork, seafood and poultry applications are possible 03, 4-7, 15, 19) Proper protein selection and hydration is critical to achieving superior finished product quality. Textured proteins have virtually no solubility and, thus, no ability to penetrate into whole muscle tissue Therefore, textured soy proteins are inherently restricted to coarse ground (e.g. sausage) or fine emulsion (e.g. weiners and bologna) products, and comminuted and reformed (i.e. restructured) meat products. None are used in whole muscle absorption or injection applications (2-4, 6, 11). 

The performance of protein additives in food products is the ultimate test of functionality (7). Functional performance, particularly moisture absorption, has been used as a criterion for selection of protein additives for food systems. Yet this has for the most part been a trial-and-error situation. The majority of data on water and fat absorption of plant protein additives in food systems has involved the incorporation of such products into comminuted meat systems. In relation to water and fat absorption, meat systems are an excellent test system. 

Torgersen and Toledo (15) assessed the relationship between solubility and water absorption of WPC, peanut protein, single cell protein (SCP), and chicken preen gland protein and characteristics in a comminuted meat system containing the various protein additives. Protein additives with high water absorption capacities were correlated with more viscous raw mixtures and with less fat and water released on cooking. Simple system determination of water absorption capacity at 90°C rather than at 78.5°C was the better predictor of water and fat retention in the food system studied. 

A few reports in the literature describe the effects of using peanut protein in comminuted meat systems such as meat loaves (, 64), frankfurters (6 ), and ground beef patties 66). In some instances, peanut protein either produced beneficial effects (e.g., increased tenderness and cohesiveness, 66) or no adverse effects from a sensory, physical, or microbial standpoint ( ). 

Comminution also may be used to examine the stability of dispersed phases such as oil droplets. Depending on the viscosity of the product one simply mixes it or breaks it up in a solvent (usually water but, for example, use fresh soybean oil for chocolate), a buffer or the appropriate dyes (below). For instance, we mix easily dispersible foods (cream cheese, ice cream mix or tablespreads) with dyes on slides in a ratio of about 1 1 before examination. Where the dye is a diachrome (that is, highly colored) or is fluorescent in the absence of the substrate (for example, Acridine Orange) some attempt must be made to remove excess, uncomplexed dye molecules which might confound the interpretation. This can be done by reduction of the dye concentration or by making the preparation thinner. The advantage of these simple techniques is that a battery of microchemical tests to identify protein, lipid and carbohydrate can be completed on multiple samples in a very short time period. 

A commercial fractionation process in which groats are dry-milled and the comminuted groats are soaked in a solution of cellulases and hemicellulases has been developed.9 In addition to the starch the process produces fiber and protein fractions. Unlike wheat starch, oat starch cannot be separated from the grain by selective hydration and centrifugation, because of hydrated bran and protein layers. 

Bianchi, M. A., Pilosof A. M. R., and Bartholomai, G. B. 1985. Rheological behaviour of comminuted meat systems containing soy protein isolates. J Texture Stud. 16 193-206. 

There are a large number of methods (Table 2) to prepare nanoparticulate systems. These depend to a large extent on the material (polymer, protein, metal, ceramic) that will form the basis of the carrier. One can, in essence, consider three approaches to their production (0 by comminution (in the case of solids, milling, and in the case of liquids, high pressure emulsification) (ii) molecular self-assembly, such as that occurs with polymeric surfactants to form polymeric micelles or with dendrons to form dendrimeric aggregates and (iii) precipitation from a good solvent as shown in Figure 6. 

Exploiting the High Compressibility of Supercritical Solvents to Comminute Proteins... 

Hydration. The ability of proteins to bind and hold water without syner-esis is critical in many foods, e.g. comminuted meat products. Although the caseins are relatively hydrophobic, they bind c. 2g H20g protein, which is typical of proteins. Hydration increases with increasing pH and is relatively independent of NaCl concentration, which is especially important in the efficacy of casein in meat-based products. The water-holding capacity of sodium caseinate is higher than that of calcium caseinate or micellar casein. 

Protein beverages Comminuted meat products Soups, sauces and gravies Hydrolyzed vegetable proteins... 

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