The hypotheses that raw fruits, whether whole or pulped, were cleared rapidly from the mouth and that the sugars in the whole and pulped fruits are fermented with equal efficiency to acids by the oral microflora were tested in this study. Groups of 7–9 adult subjects chewed 10 g of raw, whole or pulped fruit (apple, banana, orange, pear and pineapple) for 1 min and whole, unstimulated saliva samples were collected during the following 60-min interval. Each saliva sample was assayed for the concentrations of fruit-derived sugars (glucose, fructose and sucrose), fruit-derived acids (malic and citric) and acids which may be produced as a result of bacterial fermentation (acetic, lactic, formic and succinic). We found the fruit-derived sugars were rapidly cleared from the mouth (within 5 min). The major bacterially produced acids were lactic and succinic, which reached maximum concentrations in the 5-min sample. There was no significant difference, within a fruit, in the salivary levels of any of the sugars or acids between the raw whole or raw pulped forms. In light of these findings it seems unwise to assume that fruits may be consumed without consideration of their acidogenic potential.

The attempt was made in the present work to ferment the juice of unconventional fruits. Jamun (Syzgium cumini L.), pomegranate, Cocoa (Theobroma cacao L.) were chosen for the study. Fruits were collected from local market and farmers. Juice was extracted from the fruits and initial sugar was maintained between 13 to 26 °Brix. Fermentation was carried out using Saccharomyces cerevisiae at room temperature. Fixed acidity estimated in terms of tartaric acid equivalent was determined in the range of 4.2 to 6.9g/L. Radical scavenging activity of the fermented juice was between the range of 1.42 to 1.96 mmol TE/L. Metals such as Cd, Cu, Mn, Ni, Pb and Zn were estimated. Residual sugar was within 3mg/ml. Ethanol concentration was estimated in the range of 5.25 to 10.67% (v/v).