Post-mortem Biochemical Changes in the Muscle of Disk Abalone during Storage.

Abstract

The changes in content of ATP and its related compounds, free amino acids, polyamines, and D-and L-lactic acids were investigated in the muscle of disk abalone during storage at 0, 5, and 10°C in relation to freshness. ATP culminated on the 1st day of storage at 5 and 10°C. Then, a remarkable decrease in ATP and ADP was observed together with the accumulation of AMP. ATP degradation in the muscle stored at 0°C was faster than those stored at 5 or 10°C. The accumulation of AMP was most remarkable during storage at 0°C. IMP and adenosine were detected in small amounts, indicating that AMP was decomposed through two pathways. The total amounts of free amino acids in the muscle of live disk abalone ranged from 3, 600 to 4, 200mg/100g. During storage the total amounts of free amino acids increased once and thereafter decreased markedly. Though the level of L-lactic acid remained low during storage, D-lactic acid increased remarkably. D-Lactic acid was considered to be one of the main end-products in the glycolytic pathway. D-Lactic acid also ap-peared to be useful as a potential index for the freshness of disk abalone, and at the stage of initial decomposition D-lactic acid was detected at the level of 10 to 12μmol/g.