535
Chapter 42
Conventional, immunological,
Molecular, and BiosensorBased Detection Methods
introduction
Food safety and emerging food biosecurity issues are important to consumers, food manufacturers, and food producers alike. Though foodborne pathogen statistics show a slight decline in the
number of cases, outbreaks and product recalls continue to exert a huge economic burden on the
producers. Microbial populations in foods, food ingredients, and the food contact environment
normally constitute many different species coming from different sources. The total microbial
population in a food varies greatly depending upon the level of sanitation used at all phases of
production, the degree of abuse that leads to microbial growth, and the processing and preservation methods used to kill and prevent growth of microorganisms. Similarly, contamination of a
food by specific types or species of microorganisms is dependent on the presence or source of these
microorganisms and their entrance into the food, mostly as a result of poor sanitation during handling and processing. Microbiological examination of foods and food ingredients helps one assess
their safety to consumers, their stability or shelf life under normal storage conditions, and the level
of sanitation used during handling. In addition, the microbiological load and type can be important in determining whether a food and food ingredient meet acceptable standards, specifications,
and guidelines. Microbiological evaluation of raw materials also provides important information
about the heat-processing parameters that would be necessary to meet the microbiological standard,
guideline, or specification of a product. Finally, microbiological evaluation of a food, food ingredient, and environment helps determine possible sources of a specific microbial type in a food and,
in the case of a thermally processed food, the source and nature of post-heat treatment contamination. Despite all precautions, pathogens are found in ready-to-eat products, which is a serious concern because these products do not receive further treatment before consumption. In fact, several
foodborne outbreaks occurred because of consumption of undercooked or minimally processed
ready-to-eat meats (hotdogs, sliced luncheon meats, and salami), dairy products (soft cheeses made
Chapter 42
Conventional, immunological,
Molecular, and BiosensorBased Detection Methods
introduction
Food safety and emerging food biosecurity issues are important to consumers, food manufacturers, and food producers alike. Though foodborne pathogen statistics show a slight decline in the
number of cases, outbreaks and product recalls continue to exert a huge economic burden on the
producers. Microbial populations in foods, food ingredients, and the food contact environment
normally constitute many different species coming from different sources. The total microbial
population in a food varies greatly depending upon the level of sanitation used at all phases of
production, the degree of abuse that leads to microbial growth, and the processing and preservation methods used to kill and prevent growth of microorganisms. Similarly, contamination of a
food by specific types or species of microorganisms is dependent on the presence or source of these
microorganisms and their entrance into the food, mostly as a result of poor sanitation during handling and processing. Microbiological examination of foods and food ingredients helps one assess
their safety to consumers, their stability or shelf life under normal storage conditions, and the level
of sanitation used during handling. In addition, the microbiological load and type can be important in determining whether a food and food ingredient meet acceptable standards, specifications,
and guidelines. Microbiological evaluation of raw materials also provides important information
about the heat-processing parameters that would be necessary to meet the microbiological standard,
guideline, or specification of a product. Finally, microbiological evaluation of a food, food ingredient, and environment helps determine possible sources of a specific microbial type in a food and,
in the case of a thermally processed food, the source and nature of post-heat treatment contamination. Despite all precautions, pathogens are found in ready-to-eat products, which is a serious concern because these products do not receive further treatment before consumption. In fact, several
foodborne outbreaks occurred because of consumption of undercooked or minimally processed
ready-to-eat meats (hotdogs, sliced luncheon meats, and salami), dairy products (soft cheeses made