FOOD Fig. . .: Visible biological hazards in foods INVISIBLE (MICROBIOLOGICAL) HAZARDS IN FOOD PROTOZOA YEASTS MOLDS BACTERIA VIRUSES Fig. .
.: Invisible/microbiological hazards in foods Food infection /Food Poisoning results from ingestion of live pathogenic organisms which multiply in the body and cause disease. Salmonella is a classic example. This organism exists in the intestinal tract of animals. Raw milk and eggs are also sources.
Heat destroys Salmonella, however, inadequate cooking allows some organisms to survive. Often Salmonella is spread through cross-contamination. This could happen when a cook cuts raw meat/poultry on a chopping board and without cleaning uses it for another food which does not involve any cooking, such as salad. Food may become infected by Salmonella if an infected food handler does not wash hands with soap after using bathroom and before touching food.
Salmonella can reproduce very quickly and double their number every minutes. The symptoms of Salmonella infection include diarrhea, fever and abdominal cramps. Food intoxication: Some bacteria produce harmful toxins which are present in food even if pathogen has been killed. Organisms produce toxins when the food has not been hot enough or cold enough.
Toxins in food cannot be detected by smell, appearance or taste. Hence foods which smell and appear good are not necessarily safe. One example of such an organism is Staphylococcus aureus . Such organisms exist in air, dust, water.
They are also present in the nasal passage, throat and on skin, hair of per cent of healthy individuals. People who carry this organism, contaminate food if they touch these places on body while food handling. Diarrhea is also one of the symptoms of this contamination. Parasites can also cause infestation, e.g., worm infestation by tape worm in pork.
In addition to this, food can be infested by pests and insects (Fig. . ). Fig.
. : Infestation of foods Among the various hazards, biological hazards are an important cause of food-borne illnesses. In spite of all the efforts in the area of food safety, microbial food-borne pathogens are still a serious concern and new pathogens continue to emerge. Factors