A Microscopical Study of the Structure of Meat Emulsions and Its Relationship to Thermal Stability

Abstract

Meat emulsions were examined by light microscopy to determine the relationships between structure and emulsion stability. Beef-meat based emulsions were prepared either by varying chopping temperature or by adding soy plastic fats of different hardness. Formation of fat channels was observed in uncooked emulsions prepared either at a cho ping temperature of 26°C or with soft plastic fat of 0.25cm-4 hardness index. Such fat channel formations caused discontinuity of protein matrix, leading to fat separation during cooking and weakening of textural strength of products. Changes in fat globule size and distribution as affected by melting properties or hardness of fats were clearly reflected by changes in emulsion stability. Results suggest that emulsion stability is determined largely by the physical properties of protein matrix and fat incorporated. Stable emulsions were obtained with fats of appropriate melting properties and hardness and relatively cohesive protein matrix under given comminution conditions which allowed uniform fat distribution.

THERMO‐RHEOLOGY, QUALITY CHARACTERISTICS, AND MICROSTRUCTURE OF FRANKFURTERS PREPARED WITH SELECTED PLANT AND MILK ADDITIVES1

“…These observed microstructural characteristics may be due to low fat-and water-binding capacity of WGF additive in the meat system under these processing conditions. Similar results were observed in meat emulsion products with com germ flour and soy flour as additives (Lee et al 1981;Lin and Zayas 1987). These authors reported that micrographs showed void spaces and lack of compacted protein fat matrix in the wieners.…”

Characterisation and microstructure of reduced-fat chicken patties made with a novel polymer from Agrobacterium radiobacter k84

“…This organisation favours a break in the emulsion with rupture of the globules and consequent coalescence. According to the theory of a non-emulsion, the fat becomes physically enclosed in the protein matrix in this case, but only a minimal portion appears embedded in the matrix (Barbut, 2008;Lee, Carrol, & Abdollahi, 1981). Thus, the break in the structure includes the separation of fat and excretion of water from the matrix with denaturation and coagulation of the meat proteins due to heating (Aguilera & Stanley, 1990).…”

“…Thus, the break in the structure includes the separation of fat and excretion of water from the matrix with denaturation and coagulation of the meat proteins due to heating (Aguilera & Stanley, 1990). This characteristic in the F0 formulation may be due to the use of fat (chicken breast skin) in the liquid form, which may cause destabilization of the meat emulsion, because mobility is inversely proportional to consistency (Lee, Carrol, & Abdollahi, 1981). In addition, the proportion of starch used (2 g/100 g) was not sufficient to form a stable emulsion in the formulation without ARB.…”

Evaluation of textural properties of cooked beef batters

“…Lee et al (1981) found some fat globules can be present at > 20 µm in diameter suggesting comminuted meat systems should also in some circumstances be explained by the gelation theory. The gelation theory is described by Lee et al (1981) as continuous protein gel matrix.…”

“…Lee et al (1981) found some fat globules can be present at > 20 µm in diameter suggesting comminuted meat systems should also in some circumstances be explained by the gelation theory. The gelation theory is described by Lee et al (1981) as continuous protein gel matrix. The protein gel matrix is different from an emulsion in the interfacial film is the result of protein absorption on the surface of globule which is surrounded by a continuous liquid phase (Barbut, 1995).…”