Survival of Lactobacillus helveticus entrapped in Ca-alginate in relation to water content, storage and rehydration

Lactobacillus helveticus CNRZ 303 entrapped in Ca-alginate gel beads was in vestigated for improved survival and stability during fluidized-bed drying, storage and rehydration. Addition of protective solutes was very important . Studies of the conditions showed that inactivation of entrapped L. helvet icus started when the water content exceeded 0.3-0.4 g H2O (g dry wt)(-1) f or adonitol, glycerol and reconstituted non fat milk solids (NFSM), With Ri nger's solution (control) and betaine, the fall in viability was evident ab ove 1 g H2O (g dry wt)(-1). Drying down to 0.2 g H2O (g dry wt)(-1) require d the removal of 98.5-98.9% of the water. The best survival rate with the l east injured cells among survivors was experienced with adonitol and NFMS, respectively, 71% and 57% (compared to the initial) immediately after dehyd ration, Adonitol and NFMS were also best for survival during storage. The h ighest cell recovery was obtained by rehydrating the cells in cheese whey p ermeate between 20-30 degrees C done at pH 6.0-7.0, satisfying the demands for cell survival, repair and slow swelling (adaptions).