Structured Meat Products

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 reactions of the heme pigments in meat and meat products have been summarized in the scheme presented in Figure 6-13 (Fox 1966). Bilin-type structures are formed when the porphyrin ring system is broken. 

Thermal treatment of meat products ensures microbial destruction of microorganisms but also the denaturation of structural proteins, forming a gelled structure, and the inactivation of many endogenous enzymes (see Figure 21.3 above). In precooked products, characteristic color and flavor of the product are also developed during heating. Thermal treatment can be performed in forced convection ovens, both in... 

In many meat products there is a second lubricant, namely fats and oils. This result also implies that if emulsion or other fat inclusions are not fractured during chewing, then these too will have the effect of softening the structure, reducing the toughness, but will have little effect on juiciness or lubrication. Rather than aim for small droplets in highly stable emulsions, some larger droplets or even partial breakdown should be beneficial. 

Meat proteins include sarcoplasmic, myofibrillar, and connective tissue proteins. Among the sarcoplasmic proteins are heme pigments and enzymes, which influence the color, smell, and structure of meat. Myofibrillar proteins and collagen are able to retain and hold water in meat structure and to emulsify fat. Therefore they influence the rheological properties of meat products. 

Biogenic amines are dangerous to human health and legal limits are fixed in grape and wine (structures are reported in Fig. 8.13). These compounds were found in fermented foods and beverages, such as cheeses, beer and fish, and meat products (Stratton et al., 1991 Shalaby, 1996). In wine, the most abundant are histamine, tyramine, putrescine, and phenylethylamine (Radler and Fath, 1991 Lehtonen, 1996). 

The gel point in materials represents the point where behavior changes from viscous (liquid-like) to elastic (solid-like). The conditions under which this occurs are critical to such food constituents as wheat-soya solutions used as setting agents within reconstituted meat products. In this case, oscillatory-controlled stress experiments, in which a small sinusoidal stress is applied to the material, provide a convenient method for evaluating elastic and viscous properties without destroying the delicate structure of soft semisolids. 

Bourne (1975) has described texture in foods and the methods used in its measurement. The texture of meat products has been described by Purslow (1987), who stated that meat texture is affected by the structure of the solid matrix. He concluded that it is important to have a fundamental understanding of the fracture behavior of meat and how it relates to the structure of the material. The long-term aim of his studies was to explain and predict variations in the perceived texture of meat on the basis of variation in composition and structure and hopefully to able to control and optimize texture by manipulation of these factors. 

Since the Middle Ages, meat products have been subjected to many metamorphoses in food culture, the structure of meals, and economic and social factors. Still, meat is a central part of nutrition in Europe. The largest portion of the total consumption of meat in the European Union consists of pork, beef, and poultry. Also important is the consumption of meat from sheep (lamb) and goats, predominantly in Greece, followed by Ireland, Spain, and the United Kingdom. The consumption of meat from horse, rabbit, game, and other animals is lower (Deutscher Fleischer-Verband, 2003). 

Other methods that did not require sequence information but produced species-specific electrophoretic gel patterns were also developed. Single-strand conformational polymorphism analysis is one such method, which was used to discriminate fish and meat products. In this method, the same region of the DNA is amplified, double-stranded amplification products are denatured and single-stranded products are allowed to form their sequence-dependent secondary structures, and their corresponding migration patterns on the gel are observed [51]. 

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