Enamel erosive properties and fluoride content in natural fruit juice beverages available in Bangkok

Abstract

The objective of this study is to determine the acidity, buffer capacity, calcium, phosphate and fluoride contents in natural fruit juice beverages available in Bangkok. The fruits juices selected were natural, UHT beverages manufactured in Thailand with no artificial color, flavor, scent and preservatives. They were 11 kinds of grape, guava, pineapple and orange juices. Each kind was randomly selected from 5 different shops so 55 specimen were obtained. Each specimen was determined the pH, buffer capacity, calcium, phosphate and fluoride contents 3 times repeatedly. The mean and S.D. were calculated. The result showed that the averaged range of pH were 3.348 + 0.044 to 3.959 + 0.057. The averaged range of buffer capacity which were the amount of NaOH used to raise the pH of fruit juices to 5.5 and 7.0 were 22.83 + 0.588 and 42.93 + 0.729 to 85.8 + 0.368 and 103.3 – 0645 mmole/l respectively. The averaged amount of calcium and phosphate were 2.11 + 0.155 to 10.99 + 0.273 and 9.17 + 0.212 to 168.40 + 0.44 mg/100 ml respectively. The averaged fluoride content was 0.032 + 0.002 to 0.483 + 0.008 ppm. It was summarized that 11 kinds of natural fruit juice beverages selected in this study showed the

roperties because of high acidity, high buffer capacity but low calcium and phosphate content. All fruit juices had fluoride content less than 0.7 ppm which was the safe dose of drinking water.