Genetic stability of lactic acid bacteria

Careful attention must always be paid to the genetic stability of microorganisms to be used on a large industrial scale. In this context it should be noted that cultures are not just used on a large scale but on an extremely large scale. For dairy cultures used in the DVS (direct vat set) form, 1 kg of culture is used for the inoculation of W kg of milk. If this culture is produced in batches of 1(P kg each, one batch is used for the fermentation of 10 kg of milk. 

The culture manufacturer will probably not initiate each batch from a single cell isolate but rather produce inoculation material for at least 100 batches from a single cell isolate. Accordingly, the strain should be sufficiently stable to allow the production of at least 10 kg fermented milk with the desired properties from a culture initiated from a single cell 

If cultures are developed to contribute a special quality to the final product, necessary precautions need to be taken in the propagation and quality control of the cultures. Accordingly, full advantage of current research within the physiology and genetics of lactic acid bacteria can only be obtained by the use of DVS cultures. 

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