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Article Characterization of Probiotic Fermented Milk Prepared by Dif...

EPS elaboration is high when the bacteria face some kind of stress e.g. nutrient composition, growth condition  etc... if  the culture medium is same, EPS  production will remain almost same..

http://www.sciencedirect.com/science/article/pii/S0141813008001347

EPS producing lactic acid bacteria are activated at different stresses and this production phenomena are encoded genetically and more or less such trait can be lost at the first transplant

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