ABSTRACT
Microbiological examination of foods is predominantly based on culturing techniques to detect and enumerate living microorganisms. In view of the huge variety and multiplicity of groups, genera and species that may be present, a great number of tests are used, that can be classified as one of two types: qualitative tests, and quantitative tests. This chapter describes basic microbiological culturing techniques that are the detection of presence/absence, the most probable number counts and the standard plate counts. Standard plate counts are used both for quantification of large microbial groups, such as aerobic mesophilic microorganisms, aerobic psychrotrophiles, yeasts and molds, sulphite-reducing clostridia, enterococci and lactic bacteria, as well as particular genera and species, such as Staphylococcus aureus, Bacillus cereus and Clostridium perfringens. With regard to inoculation in a solid culture medium, four basic procedures may be utilized: pour plating, spread plating, drop plating and membrane filtration.
