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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-1 g-1 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 (about 64%), suggesting an
increase in membrane permeability during dehydration. During rehydration of the freeze-dried strain, 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 (from about 5% to 97%, with respect to the treatment made).
However, a decrease in the electrolyte leakage was observed with increasing glycerol, sucrose or maltodextrin and resulted
in the maintenance of cell viability. Change in membrane permeability might lead to electrolyte leakage during rehydration
and, ultimately, cell death. The electrolyte leakage assay associated with the plate count method, a quick and inexpensive
method, could be used to evaluate dried bacteria resistance to dehydration.