We compared the effects of glucose on the survival of different strains, which showed different results. L. gasseri ATCC 33323 had the best intrinsic properties in simulated gastric juice in the absence of glucose, and some strains, particularly L. rhamnosus GG, utilized glucose to survive better. Glucose has previously been shown to have different protective effects for different Lactobacillus species (7). Charalampopoulos et al. (7) showed that although Lactobacillus plantarum and Lactobacillus acidophilus experienced a protective effect from up to 8.33 g liter−1 glucose, Lactobacillus reuteri did not over 4 h of exposure. However, with the adjustment of the pH of simulated gastric juice in our study, a protective effect did occur for L. gasseri ATCC 33323 and L. paracasei NFBC 338. It is therefore not unreasonable to assume that the beneficial effect of glucose occurs for each Lactobacillus at a critical pH value. The survival of L. rhamnosus GG in simulated gastric juice in the presence of glucose also appeared to be dependent on glucose concentrations as low as 1 mM. This observation has been previously seen in lactobacilli (7).