Changes in extractive components and glycogen in the edible meat of hard clam Meretrix lusoria during storage at different temperatures

The changes in extractive components and glycogen in hard clam meat during storage at 0, 5, 10, 20 and 30 degrees C were investigated. The initial levels of ATP-related compounds, glycogen, succinic acid and free amino acids in hard clam were 3.34+/-0.19 mu mol/g, 1201+/-52 mg/100 g, 9.44+/-2.55 mu mol/g, and 1226+/-106 mg/100 g, respectively. ATP in all samples decreased markedly during storage, while the accumulation of ADP, AMP, inosine, and hypoxanthine varied depending on the 5 storage temperatures. The decrease in glycogen was common for all the samples. In contrast, succinic acid increased with time of storage, and the increase rate was faster for the samples stored at 5 and 10 degrees C. The changes in levels of free amino acids in hard clam during storage at different temperatures were inconsistent. The samples stored at 5 and 10 degrees C showed a relatively high increase in the amounts of free amino acids, particularly in alanine, taurine, and arginine. The enrichment of free amino acids and succinic acid might potentially improve the flavor quality of hard clam stored at 5 and 10 degrees C.