Food microbiology  

 

microbiology

  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.

  Food safety 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, pickles.

              Contents

     

     Foodborne pathogens   
     Foodborne
pathogens are the leading causes of illness      and death
   
     
Protozoan
     Protozoan parasites associated with food and water can      cause illness in humans
     
Mycotoxins
    Molds produce mycotoxins, which are secondary metabolites      that can cause acute or chronic diseases in humans when      ingested from contaminated foods.
    
Vibrio
   
 Vibrio species are prevalent in marine environments
  
  Staphylococcus aureus
    
Staphylococcus aureus is a common cause of bacterial     foodborne disease worldwide.    
    
Salmonella
     
infections are commonly acquired by animal to human
    
Shigella
   
Shigella species are members of the family     Enterobacteriaceae and are Gram negative
     
Escherichia coli
     
E. coli was considered a commensal of human and      animal intestinal tracts with low virulence potential.     Clostridiumbotulinum and Clostridium perfringens
    
Clostridium botulinum produces extremely potent     neurotoxins that result in the severe neuroparalytic disease,     botulism.
    
Bacillus cereus

    B. cereus is a normal soil inhabitant and is frequently     isolated from a variety of foods, including vegetables,     dairy products and meat.
    
Water activity
   
 Water activity or aw is a measurement of the energy     status of the water in a system.   
    Pasteurization
  
  Pasteurization is the process of heating liquids for the     purpose of destroying bacteria, protozoa, molds, and     yeasts.
   
Sterilization
  
 Sterilization refers to any process that effectively kills or     eliminates transmissible agents

 

 
  protozoan
salmonella