Effect of xylitol-containing carbohydrate mixtures on acid and ammonia production in suspensions of salivary sediment.

pH changes and the production of lactic acid, acetic acid and ammonia were studied in suspensions of salivary sediment supplemented with mixtures of xylitol and other carbohydrate sweeteners. The only mixtures which increased the pH values of the suspensions were those containing xylitol alone or mixtures of xylitol and sorbitol. Mixtures of xylitol and Lycasin 80/55 caused a relatively small pH reduction. Xylitol was not able to inhibit the acid production from the easily fermented glucose, fructose and Lycasin 05/60. The levels of lactic acid, determined in the incubation mixtures, directly reflected these pH changes. The levels of acetic acid and ammonia were, however, relatively similar in all incubation mixtures. The results suggest that the inhibitory effects of xylitol on acid production of oral flora should be retained, provided that xylitol is used either alone or in mixtures with slowly fermentable carbohydrates, such as sorbitol and Lycasin 80/55.