NUCLEOTIDE CATABOLISM AND CHANGES IN TEXTURE INDEXES DURING ICE STORAGE OF CULTURED STURGEON, ACIPENSER-TRANSMONTANUS

ATP depletion and other biochemical changes were related to texture indices of cooked sturgeon meat from struggled and anesthetized fish. The rates of ATP depletion, pH decline and time of rigor onset were slow in both sturgeon groups compared to other finfish. ATP depletion and accumulation of inosine and hypoxanthine were significantly faster in sturgeon allowed to struggle before death than in anesthetized fish. Penetrometer tests revealed that cooked sturgeon meat was firmer prior to ATP depletion and the onset of rigor than in the postrigor state. Fish allowed to struggle prior to death had a softer cooked meat than anesthetized fish during the first few days of iced storage. Compression tests showed that texture of cooked meat was firmest when the muscle was in rigor and also showed that meat from struggled fish was softer than that from anesthetized fish. These findings suggested that the tough texture problem, sometimes observed in fanned sturgeon, may be minimized by allowing the sturgeon meat to go through rigor prior to cooking.