Erosive Potential and Fluoride Level of Some Cultivars of Fruit

Objectives: The aim of this study was to determine and compare the pH, buffer capacity and fluoride concentration on concentrated juices of different cultivars of some fruit. Material and Methods: It was taken two cultivars of the six fruit selected: apple, orange, grape, melon, pineapple and tangerine. The samples were processed in triplicate. The fruit were grinded with Walita mixer (model HL 3235) to obtainment of juices and, after, the same were centrifugated in Sigma centrifuge (model 4k 15), at 19^oC, in 5100 rpm, for 15 min. The measurement of pH and the fluoride concentration were performed with microprocessed potenciometric machine (ANALION – AN 2000). The buffer capacity was determined adding aliquots of 0.05N NaOH to 4mL of sample, being used phenolphtaleine as acid-base indicator. Results: The results of pH to different cultivars were: Fuji apple (3,87); Red Delicious apple (4,16); Bahia orange (4,66); Valência orange (3,71); Bordô grape (3,36); Rubi grape (3,55); Gaúcho melon (5,97); Spanish melon (5,19); Pérola pineapple (3,45); Smooth Cayenne (3,61); Monte Negrina tangerine (3,31); Poncan tangerine (4,39). It was observed a few variation in the values of pH between the fruit and their respective cultivars. The free ionic fluoride level didn′t surpass 0,38mg.L^-1. The pineapple cultivars showed the biggest buffer capacity. Conclusion: It was concluded that the majority of fruit juices from different cultivars showed potential of demineralization on dental tissues and the fluoride level in these juices was inexpressive.