Figure 2. Desirable and undesirable bioactive metabolites produced during fermentation which can impact choice of starter cultures.

Fermentation starters can produce a number of desirable and undesirable bioactive metabolites. Biogenic amines (left) are an undesirable product in most fermentations due to their toxicity. Bioactive peptides (right) produced through enzymatic release are desirable by-products due to positive biological activity. Bacteriocins (centre) are desirable as a known probiotic trait, but potentially undesirable in a starter culture due to possible impact on other fermenting cultures.