EFFECT OF ADDITION OF 0.103-PERCENT CITRATE TO A BLACK-CURRANT DRINK ON PLAQUE PH IN-VIVO

The aim of the present study was to investigate whether the addition of a small amount of citrate to infant fruit drinks resulted in a similar beneficial effect to that reported recently with 10% sucrose solution. A popular blackcurrant drink was tested with and without added 0.103% citrate by measuring its ability to depress plaque pH in 20 adult subjects using the plaque-harvesting technique. Solutions of 10% sucrose and 10% sorbitol were used as positive and negative controls, respectively. The results showed that the blackcurrant drink with added citrate had a significantly weaker plaque pH response as compared with the blackcurrant drink without added citrate and 10% sucrose (positive control). The mean areas enclosed by the pH curve below pH 6.0 (+/-SD) were 10% sorbitol (negative control) 0.00, blackcurrant with 0.103% citrate 1.85 +/- 1.07, plain blackcurrant 4.65 +/- 2.11, and 10% sucrose 6.25 +/- 2.35. The acidogenic potential of the blackcurrant drink with added citrate was less than half as compared with the plain blackcurrant drink. It was concluded that the addition of relatively low levels of citrate to a blackcurrant drink reduces the acidogenic response in plaque.