Streptococcus thermophilus is a thermophilic Gram-positive
microorganism which belongs to the lactic acid bacteria group
(LAB). It is used for production of fermented milks such as yogurt
and for the production of some Italian and Swiss type cheeses, such
as Mozzarella and Emmental (Iyer, Tomar, & Singh, 2010). The
main roles of S. thermophilus in milk fermentation are to utilise galactose
and provide rapid acidification with lactic acid production.
Several other important technological properties, such as sugar
metabolism, proteolytic activity, and urease activity are also
known, and represent the degree of phenotypic diversity existing
within the species. At the end of metabolic activities, some LAB
strains can produce toxic compounds such as biogenic amines
(BA) (Ladero et al., 2012).