Effects of Rested Harvesting on Muscle Metabolite Concentrations and K-Values in Chinook Salmon (Oncorhynchus tshawytscha) Fillets during Storage at 15 degrees C

Improvement of harvesting procedures in aquaculture may also improve the quality and storage properties of the fish. The use of an anesthetic allows fish to be harvested with reduced stress and exhaustion, which affect fillet properties. We report here on the effects of rested harvesting on the postharvest metabolic profiles and K-values in Chinook salmon (Oncorhynchus tshawytscha) fillets stored near to the fish's acclimation temperature at 15 degrees C for 36 h. Fresh rested fillets were obtained by anesthesia with AQUI-STM. They had high cut surface pHs (7.63) and high concentrations of adenosine triphosphate (ATP) and creatine phosphate (3.75 and 8.73 mu mol g(-1) respectively), which depleted over 12 h. In contrast, fresh exhausted fillets had low cut surface pHs (6.66) and ATP and creatine phosphate were depleted. Adenosine diphosphate (ADP) and beta-nicotinamide adenine dinucleotide (NAD(+)) concentrations also remained significantly higher during the first 12 h of storage in rested fillets. In fresh rested fillets inosine monophosphate (IMP) concentrations reached maximum after 12 h storage (4.78 mu mol g(-1)), whereas maximum IMP concentrations occurred immediately postharvest in the exhausted fillets (6.42 mu mol g(-1)). After 36 h storage, K-values in exhausted fillets reached 52.11% compared to 19.27% in rested fillets. Rested harvesting of Chinook salmon improved the fillets' metabolic potential postharvest, extending metabolite depletion times, changing IMP concentrations and reducing K-values.