Quality changes during freezing and frozen storage of mackerel (Rastrelliger kanagurta) and pink perch (Nemipterus japonicus) in summer season.

摘要

The study has been conducted to assess the effect of freezing and frozen storage on the quality of chilled mackerel (Rastrelliger kanagurta) and pink perch (Nemipterus japonicus) in air blast freezer, freezing and subsequent frozen storage at -18 C. This difference in the freezing of mackerel and pink perch could be attributed to the varied quality of these two samples. Upon freezing, the moisture content and protein content decreased in both the samples. But lipid content remained in the increasing order. Upon freezing and during frozen storage, lipid oxidation products (peroxide value, thiobarbituric acid value and free fatty acid value) and volatile bases (total volatile base nitrogen and trimethyl amine nitrogen) showed an increasing trend in both the samples with values slightly higher in mackerel samples compared to pink perch frozen samples. The total plate count did not show any significant difference in both the samples.