Food microbiology is the study of the microorganisms which inhabit, create or contaminate food. Of major importance is the study of microorganisms causing food spoilage. However "good" bacteria such as probiotics are becoming increasingly important in food science. In addition, microorganisms are essential for the production of foods such as cheese, yoghurt, other fermented foods, bread, beer and wine.
is a major focus of food microbiology. Pathogenic bacteria,
viruses and toxins
produced by microorganisms are all
possible contaminants of food. However, microorganisms and their products can also
be used to combat these pathogenic microbes. Probiotic
bacteria, including those which produce bacteriocins
can kill and inhibit pathogens.
Alternatively, purified bacteriocins
such as nisin can be added directly to food
products. Finally, bacteriophage,
viruses which only infect bacteria,
can be used to kill bacterial pathogens.
Thorough preparation of food, including proper cooking will eliminate most bacteria and
viruses. However, toxins produced by contaminants may not be heat-labile, and
some will not be eliminated by cooking.
Fermentation is one way
microorganisms can change a food. Yeast,
especially S. cerevisiae,
is used to leaven bread, brew beer
and make wine. Certain bacteria,
including lactic acid
bacteria, are used to make yogurt,
cheese, hot sauce,
are the leading causes of illness
parasites associated with food and water can cause illness in humans
produce mycotoxins, which are
secondary metabolites that can cause acute or chronic diseases in humans when ingested from contaminated foods.
Vibrio species are prevalent in marine
Staphylococcus aureus is a common cause of bacterial foodborne
infections are commonly acquired by animal to
Shigella species are members of the family Enterobacteriaceae and
are Gram negative
E. coli was considered a commensal of human and animal
intestinal tracts with low virulence potential. Clostridiumbotulinum and Clostridium
Clostridium botulinum produces extremely potent neurotoxins that result in the severe
neuroparalytic disease, botulism.
B. cereus is a normal soil inhabitant and is frequently
isolated from a variety of foods, including vegetables, dairy products and
Water activity or aw is a measurement of the energy status
of the water in a system.
Pasteurization is the process of heating liquids
for the purpose of destroying bacteria, protozoa, molds,
Sterilization refers to any process that
effectively kills or eliminates transmissible agents