The effect of different concentrations of sugars in two foods (yoghurts and baked beans) on plaque pH.

The effect of different concentrations of sugars in two foods (strawberry yoghurt and baked beans) on plaque acidogenicity was investigated using plaque sampling with a 'Beetrode' electrode. Six varieties of yoghurt, four varieties of baked beans and positive and negative control solutions of 10 per cent sucrose and sorbitol, respectively, were tested on six volunteers, selected according to the guidelines agreed at the San Antonio Conference of 1985. Plaque was harvested immediately before a one minute challenge with the test condition and at 5, 10, 15, 20 and 30 minutes thereafter. Parameters investigated were minimum plaque pH reached after a one minute consumption/rinse of the test food or control solution, maximum drop in plaque pH and 'area of the Stephan curve below pH 6.5'. An Acidogenic Potential Index was calculated for each test food and the results did not suggest a linear relationship between sucrose concentration in a food and acidogenic potential.