摘要：Conjugated linoleic acid ( CLA ) is a fatty acid which it can be synthesised by ruminant microorganisms. Some of the ruminant microorganisms which have probiotic properties are used as commercial starter cultures especially in yoghurt and at small scales as a test production of cheese and butter in last years. These microorganisms able to synthesis free linoleic acid and then conjugated linoleic acid from the linoleic acid, during ripening period. The most important bacteria that can be synthesis CLA are Lactobacillus , Propionibacterium , Bifidobacterium and Enterococcus strains. It was determined that CLA isomers have anticarsinogenic , antiatherogenic , antidiabetic , enhance immune system, regulation of fat, muscle and mineral matter composition in metabolism. In addition varieties of starter bacteria, many factors can be affected the changes in the amounts of CLA in dairy products. Some of the these factors are substrate concentration, incubation period, culture pH, bacteria genes, in addition type and age of the dairy animal, changes of the climatic conditions, fat amounts of the product and using food additives. In this study, CLA formation affecting factors, some CLA producing bacteria and CLA formation in dairy products were discussed. Choosing as commercial starter culture containing lactic acid bacteria that having ability to produce high levels of CLA can be increased nutritive value of dairy products.
