"cathep" - 1 õppematerjal

Liha töötlemine

circulatory competency after harvest requires 1979). During the immediate postmortem that the tissues shift to anaerobic metabolism, period, tissues metabolize glycogen via resulting in the accumulation of metabolic anaerobic pathways, lowering pH. ATP is byproducts, including lactic acid, in the rapidly consumed, but as reducing equiva- muscle. The pH declines from about 6.8 to lents are consumed, it is not regenerated. 5.7. Endogenous thiol proteinases (cathep- Without the plasticizing effect of ATP, actin sins B and L) become activated near pH 5.4. and myosin cross-link, the sarcomere short- They are redistributed (intracellularly) during ens, fibers contract, and rigor results. During aging (Spanier et al. 1990; Spanier and Miller the rigor process, muscle cells undergo both 1993). Proteolytic enzyme activity is temper- longitudinal and lateral contraction, usually