Bacteriological Quality of Fresh and Ice-stored Farmed Macrobrachium rosenbergii

Abstract

Farmed freshwater Scampi (Macrobrachium rosenbergii de Man) collected from four different farms in central Kerala were analysed for bacteriological quality immediately after harvest and after icing for two weeks. Aerobic mesophilic bacteria (TPC), faecal streptococci, faecal coliforms, Escherichia coli and Staphylococcus aureus were enumerated. Total aerobic mesophilic bacterial counts (TPC) on fresh prawn (whole) were of the order of 106 to 107 cfu g"1. The TPC of fresh and ice stored prawn (whole and headless) were within the acceptable limit. The levels of faecal streptococci and faecal coliforms in fresh M. rosenbergii were above the acceptable limits. However, faecal coliform and E. coli numbers werewithin the limit (<100 cfu g"1) in deheaded prawn during iced storage. Presence of excessively high TPC and faecal streptococci numbers has been a major microbiological problem in freshwater prawn. This study revealed that A. hydrophila, A. veronii biovar sobria and Enterococci grew well at refrigerated temperatures. A. hydrophila, A. veronii biovar sobria, S. putrefaciens and Pseudomonas were identified as potent spoilers of farmed M. rosenbergii