Quality Changes in Australian Red Claw Crayfish, Cherax quadricarinatus, Stored at 0deg C

摘要

Shell-on tails of 70 juvenile Australian red claw crayfish, Cherax quadricarinatus, were separately packaged in seven sealed plastic freezer bags (10 in each) and stored on ice (0deg C) for 0,1, 3, 5, 7,10, and 14 days. At the end of each storage period, raw muscle homogenate from five tails (pooled) were analyzed for lipid peroxidation, proteolysis (electrophoreis), and thermal stability (differential scanning calorime-try). The other five tails were individually cooked (2 minutes boiling) to determine cooking yield and toughness (Warner-Bratzler shear). Lipid oxidation occurred during storage (e.g., TBA values increased from 0.341 mg/kg on day 0 to 1.492 mg/kg on day 14, P < 0.05). Myofibrillar and sarcoplasmic proteins were generally resistant toproteolysis, but were destabilized during storage. Transition temperatures for myosin head and actin decreased (P <= 0.05) from 50.2deg C and 72.6deg C on day 0, to 39.4deg C and 60.3deg C by day 14, respectively; while enthalpy of denatur-ation for myosin head reduced from 0.324 J/g to 0.116 J/g during this period. Storage also resulted in a gradual loss in cooking yield, which correlated (R = -0.82, P < 0.05) with progressive toughening of cooked meat. The results indicate that red claw muscle is susceptible to protein denaturation and lipid oxidation, and these chemical changes may be responsible for decreased cooking yield and reduced tenderness of meat during extended refrigeration storage.