The moisture content of probiotic products is another factorinfluencing shelf-life stability of live bacteria. Storage in the presence of both oxygen and moisture was detrimental for bacterial survival(nneby et al., 2013). The amount of water remaining after drying affects not only the viability of bacteria as determined immediately after the process, but also the rate of loss of viability during subsequent storage. The optimum moisture content for storage of freeze-dried L. salivarius subsp. salivarius was reported to range between 2.8% and 5.6% (Zayed & Roos, 2004). Increasing the relative humidity of the environment at which the samples were stored caused an increase in water mobility and the rate of loss in viability (Ying et al., 2010). Weinbreck et al. (2010) reported that a water activity of 0.7 resulted in 10 log cycle reduction in viable conuts of L. rhamnosus GG within 2 weeks of storage. Hoobin et al. (2013) suggested that moisture uptake properties and molecular mobility of the matrix composition, as opposed to the relative humidity of the environment, are better determinants of probiotic viability during storage.