Glycolysis in Lingcod Muscle During Frozen Storage

The lactic acid content and several acid-soluble phosphorus-containing fractions of lingcod muscle have been measured after periods of storage of up to 6 months at storage temperatures between 0 and −30 °C. The fish were killed in an unexercised condition and frozen either in liquid nitrogen or at the temperature of storage. Glycolysis, as indicated by lactic acid accumulation, clearly proceeded at temperatures down to and including −20 °C, and some evidence was obtained to indicate that it may proceed at a very low rate indeed (of the order of 0.5 μmole lactic acid formed/g of muscle/month, or less) at a temperature of −30 °C. Acid-labile and acid-soluble phosphorus decreased during storage at temperatures down to and including −20 °C in muscle frozen by either procedure, but only in the more slowly frozen muscle at −30 °C. Acid-stable and acid-soluble phosphorus decreased at temperatures down to −20 °C, but not at −30 °C.