Meat shear cell

Stanley (1976) found that, for a Warner-Bratzler shear cell, the firmness of a meat product may be reflected by measurements in compression, whereas tenderness may be reflected by the tensile strength of the meat. He further indicated that firmness and tenderness may or may not be dependent on each other. For this reason, results from such tests may be difficult to interpret. 

Meat tenderness has been measured with the shear press. This can be done with the 10-blade universal cell or with the single-... 

Basically, there are three major groups of proteins in muscle tissue (a) the sarcoplasmic proteins of the muscle cell cytoplasm, (b) the myofibrillar proteins, soluble at high ionic strengths, that make up the myofibril or contractile part of the muscle, and (c) the stromal proteins comprised largely of the connective tissue proteins, collagen, and elastin. The myofibrillar proteins and the stromal proteins are fibrous and elongated they form viscous solutions with large shear resistance. These properties coupled with other lines of indirect evidence indicate that the physical properties of the myofibrillar and stromal proteins are directly related to the texture and tenderness of meat (34). 

Expanders. Sometimes low shear extruders called expanders are used. This equipment has the capability to process both low- and high-oil content materials. The meats are fed into an extruder after dehulling, flaking, and cooking and are heated as they are conveyed by a screw press through the extruder barrel. The meats are under considerable pressure and temperature when they reach the exit of the extruder. The change in pressure as the material leaves the extruder causes it to expand and the oil cells are ruptured, releasing the oil, which is rapidly reabsorbed. The expanded collets produced are then cooled and extracted with solvent. 

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