Change In Proximate Composition And Microbial Count By Low Temperaturepreservation In Fish Muscle Of Labeo Rohita(HamBuch)

Abstract

The study was designed to investigate the effect of low temperature preservation on the chemical and microbial profile of fish muscle (Labeo rohita) stored for a period of twenty one days. The proximate composition and microbiological analyses were carried out at 7 days interval on muscle of fish during frozen storage. It was found that the protein, lipid, moisture and ash contents decreased significantly (P < 0.05) during the entire storage period. In fresh (unfrozen) samples, protein(15.93±0.04%), fat (3.86±0.04% ), moisture (84.74±0.1%.),and ash content (1.79±0.01%) were found to be the highest ,where as the total percent decrease in frozen samples on 21 st day of frozen storage was (12.99% ), (22.27%) , ( 4.60% ) and (24.02% ) for protein, fat, moisture and ash respectively. The microbial count increased gradually during the period of storage. The Total Plate Count in fresh fish muscle on day zero was rather low i.e. 2.44±0.2 log cfu/g as compared to the values found on the 21 st day i.e. 5.10±0.02 log cfu/g. The Coliform Count also followed the same trend during the storage. On day zero, a few colonies were found and the CC was 1.50±0.15 log cfu/g where as it increased up to 3.08±0.07 log cfu/g on last day of storage. Similarly Psychrophillic count increased from 2.15±0.2 log cfu/g on day zero to 5.06±0.05 log cfu/g on 21 st day. Thus, a significant quality loss was observed in fish during storage. However, the present frozen conditions retained the fish under acceptable microbial conditions for human consumption up to 14 th day beyond which it became unfit for human consumption.