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 o f a small amount of citrate to infant fruit drinks resulted in a simil ar beneficial effect to that reported recently with 10% sucrose soluti on. A popular blackcurrant drink was tested with and without added 0.1 03% citrate by measuring its ability to depress plaque pH in 20 adult subjects using the plaque-harvesting technique. Solutions of 10% sucro se and 10% sorbitol were used as positive and negative controls, respe ctively. The results showed that the blackcurrant drink with added cit rate had a significantly weaker plaque pH response as compared with th e blackcurrant drink without added citrate and 10% sucrose (positive c ontrol). The mean areas enclosed by the pH curve below pH 6.0 (+/-SD) were 10% sorbitol (negative control) 0.00, blackcurrant with 0.103% ci trate 1.85 +/- 1.07, plain blackcurrant 4.65 +/- 2.11, and 10% sucrose 6.25 +/- 2.35. The acidogenic potential of the blackcurrant drink wit h added citrate was less than half as compared with the plain blackcur rant drink. It was concluded that the addition of relatively low level s of citrate to a blackcurrant drink reduces the acidogenic response i n plaque.