Food Safety @ Geneva

bacteria are the numerous microorganisms that are associated with the preservation of various foods. In many cases such as fermented fruits and vegetables, meats, wines and dairy foods, the microorganisms responsible for carrying out the conversion of normally perishable foods to long lasting to indefinite storage are the group of Lactic Acid Bacteria. As the lactic acid bacteria ferment the foods, their end products in combination with the limitation of available nutrients prevent typical spoilage of the food.

Typical lactic acid bacteria that ferment foods are:

Lactococcus lactis

Bifidobacterium bifidus

Lactobacillus acidophilus

Leuconostoc plantarum

Pediococcus acidlactici

Leuconostoc eonos

The type of organism that will carry out the fermentation and subsequent preservation depends on the type of food. For example, Leuconostoc plantarum is involved in the fermentation of cabbage to sauerkraut and Lactococcus lactis is typically involved in dairy fermentations.

The number of organisms in fermented foods can be over 100 000 000 per gram of food. The high levels of bacteria are not a danger since they are not capable of causing disease in healthy people. Some lactic acid bacteria have been shown to have health benefits when consumed on a regular basis (Lactobacillus acidophilus and Bifidobacterium bifidus). It is postulated that these bacteria are capable of colonizing the gut where they are able to maintain a healthy bacterial population and preventing the infection by pathogens.