Contradictory results have been reported regarding the
influence of stimulating factors on EPS production. Enhanced
EPS production and growth were obtained when hydrolyzed
casein was added to skim milk cultures of Lactobacillus bulgaricus
(14). According to Schellhaass (27), neither growth nor
EPS production was specifically linked to the presence of
casein or whey proteins in the growth medium of thermophilic
and mesophilic lactic acid bacteria. However, Cerning et al.
found that casein stimulates EPS production but not growth of
Lactobacillus bulgaricus (7). It has also been reported that
Lactobacillus bulgaricus is able to produce the same amount of
EPS in milk and milk ultrafiltrate, but that S. thermophilus is
not (9). On the other hand, supplementation of milk ultrafiltrate
with glucose or sucrose stimulates EPS production by
Lactobacillus casei and modifies the composition of the EPS