Effect of Fermentation Conditions (culture media and incubation temperature) on Exopolysaccharide Production by Streptococcus thermophilus

2nd International Conference on Biology, Environment and Chemistry (ICBEC). 28-30 december, 2011, Dubai, United Arab Emirates.
This work investigates the influence of incubation temperature and culture media on exopolysaccharides (EPS) production. The S. thermophilus BN1 an EPS-producer strain isolated from cow milk was examined in this study. Skimmed milk, whole milk and cheese whey, were selected as culture media and two different temperatures were also tested. The EPS produced in the different studied conditions was purified and quantified. The strain BN1 was able to produce EPS in all established conditions. However, significant differences were observed in the amounts of produced EPS. The production of EPS reached the maximum values at 37°C in skimmed milk with amount of 548 PDM mg l-1, followed by the amounts of 375 PDM mg l-1 and 325 PDM mg l -1 respectively in whey and whole milk. In addition, a slight significant difference was noted on the biomass, pH and lactic acid values obtained from the three fermented substrates (p