Meat texture

Q The most detailed studies were reported by Hermansson and Akesson ( , 41) and Hermansson (42) in which the properties of a soy isolate, caseinate, WPC, and model test systems of additive and lean beef or pork were studied. Solubility, swelling, and viscosity (properties reviewed as related to water absorption) were correlated with moisture loss in the raw systems. In cooked systems, the best predictability of meat texture as affected by additive was a statistical model that included the functional properties of swelling and gel strength of protein additive dispersions. 

Meat texture is usually described in terms of tenderness or the lack of it—toughness. This obviously is related to the ease with which a piece of meat can be cut with a knife or with the teeth. The oldest and most widely... 

Purslow, P.P. (1991). Measuring meat texture and understanding its structural basis. In Vincent, J.F.V., and Lillford, P.J. (eds.). Feeding and the Texture of Food, Cambridge University Press, Cambridge, pp. 35-56. 

Microbiological nutrient gelforming agent emulsifier bread staling retardant meat texturizer meat substitute... 

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. 

Stanley (1983) stated that many researchers now believe the major structural factors affecting meat texture are associated with connective tissues and myofibrillar proteins. Therefore, he suggested that these structures merit particular attention. He concluded that two other components, muscle membranes and water, also deserve consideration, not because of their inherent physical properties, but rather as a result of the indirect influence they have on the physical properties. It should be noted that sarcoplasmic... 

The response of serum lipid patterns in healthy young men to the ingestion of HEAR oil and LEAR oil was studied in a series of four metabolic studies in the Department of Foods and Nutrition at the University of Manitoba. The subjects, who were either students or employees of the University, resided In their own homes and maintained their usual activity patterns but ate all their meals in the Department. The experimental diets in these studies were designed so dietary fat could be carefully controlled and yet the diets consist of familiar foods (Bruce and McDonald, 1977). Fat supplied about 38-40% of the total energy in the diets, with the specific fat being studied supplying about 95% of this total. The diets consisted of customary foods but contained no meat. Textured soybean protein, egg albumen, and skim milk were the main protein sources. Soy protein was incorporated into en-... 

Fats of high melting point contribute significantly to the textural stabiUty of many sausages and meat mixtures, eg, the smearabiUty of pBtH de foie gras in contrast to the soHdity of summer sausage. 

Soybean products that have been processed to remove a portion or all of the carbohydrates and minerals are used to make textured vegetable proteins which can be formed into various shapes and textures (see Soybean and other oilseeds). Many canned dog foods utilize the textured vegetable protein chunks with added juices, flavor enhancers, vitainins, and minerals to produce canned dog foods that have the appearance of meat chunks. 

Protein-Based Substitutes. Several plant and animal-based proteins have been used in processed meat products to increase yields, reduce reformulation costs, enhance specific functional properties, and decrease fat content. Examples of these protein additives are wheat flour, wheat gluten, soy flour, soy protein concentrate, soy protein isolate, textured soy protein, cottonseed flour, oat flour, com germ meal, nonfat dry milk, caseinates, whey proteins, surimi, blood plasma, and egg proteins. Most of these protein ingredients can be included in cooked sausages with a maximum level allowed up to 3.5% of the formulation, except soy protein isolate and caseinates are restricted to 2% (44). 

Oilseed proteins are used as food ingredients at concentrations of 1—2% to nearly 100%. At low concentrations, the proteins are added primarily for their functional properties, eg, emulsification, fat absorption, water absorption, texture, dough formation, adhesion, cohesion, elasticity, film formation, and aeration (86) (see Food processing). Because of high protein contents, textured flours and concentrates are used as the principal ingredients of some meat substitutes. 

Meat Products. Citric acid is used in cured meat products to increase the effectiveness of the antioxidant preservatives, as a processing aid, and a texture modifier. It is often encapsulated and released at a specific temperature from a controlled release matrix. 

For us to remain perfectly healthy, the protein in our diet must supply suffident quantities of amino acids. We prefer to eat our protein in particular forms, that is in foods having particular textures, tastes and smells (these are called organoleptic properties). Conventional sources of protein are plants, mainly as cereals and pulses, and animals, mainly as meat, eggs and milk. The proportions of such proteins eaten in various parts of the world differ widely (Figure 4.1). 

The functions of nitrite added to meat for the purpose of curing are now well known by many people because of the extensive publicity given to the process via the popular press. Nitrite added to meat results in a typical color and a characteristic flavor, provides microbiological protection especially against outgrowth of C. botulinum spores and may play a role in textural characteristics. 

Beilken et al. [ 12] have applied a number of instrumental measuring methods to assess the mechanical strength of 12 different meat patties. In all, 20 different physical/chemical properties were measured. The products were tasted twice by 12 panellists divided over 4 sessions in which 6 products were evaluated for 9 textural attributes (rubberiness, chewiness, juiciness, etc.). Beilken etal. [12] subjected the two sets of data, viz. the instrumental data and the sensory data, to separate principal component analyses. The relation between the two data sets, mechanical measurements versus sensory attributes, was studied by their intercorrelations. Although useful information can be derived from such bivariate indicators, a truly multivariate regression analysis may give a simpler overall picture of the relation. 

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