What it does
The culture competes for nutrients and space, and many strains also produce bacteriocins and organic acids that inhibit specific spoilage and pathogenic organisms. The effect is a microbiological hurdle created by competition rather than by a chemical preservative, and it declares as a culture rather than as an additive.
Where it works
Chilled products where shelf life is limited by microbiology and the label has to stay short: cooked meat, fresh cheese, chilled prepared foods. It is one of the few genuine answers to the demand for longer shelf life and fewer ingredients at the same time.
Where it does not
It is not a rescue for poor hygiene or a broken cold chain, and it will not make a contaminated product safe. The culture is alive, so it needs the right temperature and pH to do anything, and a frozen or heat treated product may kill it before it works. Some strains will also alter flavour slightly over shelf life.
What it interacts with
Temperature and pH, decisively. Other preservation hurdles, with which it is designed to be combined rather than to replace.
