Microbiological Methods for Food Analysis

Abstract

Microbiological analysis of food and food products is important as growth of microbes occurs in food contaminated with pathogenic bacteria and fungi which critically affects the quality of food and farm products. These pathogenic microorganism in food products has hazardous effects on human health. Since, microbiological parameters have been established as the responsible factors for food safety, hence, microbiological evaluation for food safety are the key subjects in the current era. Major objectives of microbiological analysis of food are to evaluate the presence and absence of different types of microbes recommended for analysis and determining their nature in terms of pathogenicity and toxicity. It is also worthwhile to know about different categories of levels of contamination of microbes in food. The method adopted for analysis may vary from product to product based on the level of contamination. Ingredients and water used for food preparation should also be evaluated for microbial testing in addition to final cooked food. Quality of water and ingredients is necessary for determining the suitable system and measures to ensure the safety & quality of finished food products. In this chapter, various microbiological methods such as total bacterial count, total coliform count, total yeast and mold count, enumeration of E. coli, S. aureus, Bacillus cereus in food and food products have been described. The detection and identification of specific pathogen such as Escherichia coli, Salmonella, S. aureus, Shigella, Vibrio cholerae, Vibrio parahaemolyticus, Clostridium perfringens in food and food products are deliberated. Current chapter also describes method of identification of E. coli O157: H7, osmophilic bacteria, Enterobacter sakazakii, thermophilic acidophilic bacteria (TAB) in food and food products.