ABSTRACT
Fish and shellfish harbor a wide variety of microorganisms, and those responsible for their spoilage are mainly gram-negative bacteria. Numbers and types of micro-organisms present in aquatic food products are indicators of safety and quality. Aerobic plate count (APC) or total viable count or total plate count or standard plate count provides an estimate of the total number of aerobic microorganisms in foods. APC of fish products indicates quality, shelf life, and post-heat-processing contamination, rather than food safety hazards. Classical microbiological methods can also detect the presence of pathogenic bacteria. The method employs enrichment and isolation of presumptive colonies of bacteria on solid media, followed by the final confirmation of bacteria by biochemical and serological methods. Streptococci are gram-positive, non-motile, non-sporing, facultatively anaerobic and catalase-negative cocci. They grow only in media containing fermentable carbohydrates or those enriched with blood or serum.
