Changes in Membrane Permeability During Rehydration of Freeze-Dried Weissella paramesenteroides LC11

The objective of this study was to assess changes in membrane permeability during rehydration of freeze-dried Weissella paramesenteroides LC11. Viability was assessed using the electrical conductivity measurement (ms/cm/g dry weight) and the plate count method (cfu g-1 dry weight). The symptoms of injury included an increase in the electrolyte leakage during the first 4 h of rehydration in Milli Q water and a decrease in the survival rate, suggesting an increase in membrane permeability during dehydration. An increase in the temperature, NaCl or monosodium glutamate concentration and a decrease in H+ concentration resulted in an increase in the electrolyte leakage and a decrease in the survival rate. However, a decrease in the electrolyte leakage was observed with increasing glycerol, sucrose or maltodextrin and resulted in the maintenance of cell viability. Regression analysis showed that overall, there was a good correlation between the survival rate and electrolyte leakage (R2>0.90). Change in membrane permeability might lead to electrolyte leakage during rehydration and ultimately, cell death.