Changes in ATP and Related Breakdown Compounds in the Adductor Muscle of “Itayagai” Scallop Pecten albicans during Storage at Various Temperatures

Abstract

Striated adductor muscle samples (11.6g on average) of “itayagai” scallop Pecten albicans were stored at -3, 0, 5, and 10°C, and examined for changes in ATP and related breakdown compounds. After 6h of storage at -3 and 0°C, ATP disappeared and ADP decreased down to 10% in its molar ratio to the total of ATP and related compounds. At 5 and 10°C, ATP and ADP decreased more slowly, maintaining the levels of 7-13% and 21-29%, respectively, even after 48h. These degradation patterns of ATP at different temperatures as a whole, resembled those reported for fish. On the other hand, K value, a freshness indicator defined as the molar ratio of inosine plus hypoxanthine to the total of ATP and related compounds, increased faster at -3 and 0°C than at 5 and 10°C. However, the adductor muscle resulted in the worst organoleptic evaluation when stored at 10°C.
When unshucked itayagai scallop was stored at 5°C, adductor muscle ATP remained at a high level (-4μmol/g) for a few days, then sharply decreased probably in association with death, as did the isolated adductor.