Inhibition of Streptococcus mutans's acid production by erythritol in milk-an in vitro study

AIM: To study the inhibitory effect of erythritol on acid production of Streptococcus mutans in milk.METHODS: Erythritol at 2%,4%,6% and 8% in fresh milk was prepared,milk without erythritol was used as the negative control and phosphate buffer as the blank.The solutions were sterilized.Streptococcus mutans were then cultured in the solutions in a anaerobic environment.The pH value were measured at 0,2,4,6,8,10 and 12 hours of culture,data were analysed by SPSS 16.0.RESULTS: At all the time points pH values of blank control group was the higherst and that of the negative control the lowest.pH values in all the cultures declined during 0 ～ 4 hours.After 6 hours,the pH value of the negative and blank groups continued to fall,but the that of erythritol-milk groups did not change significantly.pH values of 6% and 8% erythritol-milk groups showed no significant difference at all tme points(P 0.05),but higher than those of 2% and 4% groups after 6 hour culture(P 0.05).CONCLUSION: Erythritol may inhibit the acid production of streptococcus mutans in milk in a concentration dependent manner.