ASSAD, Andressa de Marchi El et al. Determination of pH, buffering capacity, total carbohydrates and sucrose in sugar-free and light processed fruit juices. RSBO (Online) []. 2010, 7, 3, pp. 281-286. ISSN 1984-5685.

INTRODUCTION: Tooth erosion is the irreversible loss of dental hard tissues caused by acids and/or chelation without bacterial involvement. Many studies showed that there is an increase of tooth erosion in population and that it is related to the consumption of soft drinks, including processed fruit juices. OBJECTIVE: The aim of this study was to evaluate the pH, buffering capacity (BC), total carbohydrates and sucrose in 15 sugar-free and light processed fruit juices. MATERIAL AND METHODS: The pH was determined with a Mettler Toledo 320 pH meter. The BC was determined by titration, adding 0.1 N NaOH in 10 mL of each drink until reaching a pH level of 7.0. The total carbohydrates were determined using the phenol sulfuric method, while the sucrose was determined through the incubation of each sample with the invertase enzyme. RESULTS: The average value of pH was 2.61 (±0.29). The processed fruit juices analyzed needed, in average, 6.2 mL (±1.9) of NaOH in order to increase the pH to 7.0. The total carbohydrates showed to be according to the values presented in the labels. The sucrose content verified in each drink was very low and varied from 0.60 to 0.93 g / 200 mL. CONCLUSION: This study showed that the 15 drinks analyzed had low pH and erosive potential, once most juices presented high BC. The sucrose presented in each drink was very low, suggesting that they are not cariogenic. Nevertheless, further studies that demonstrate the action of these juices in the dental surface are required.

: fruit juices; tooth erosion; pH.