Determinação do teor de ácido cítrico em refrigerantes de guaraná e a sua influência na causa da erosão dentária.

Abstract

Soda is a beverage made of industrially pure carbon dioxide, obtained by dissolving in drinking water, fruit juice from its source, added sugar. The acids contained in the drink have a role to enhance the taste and inhibit the action of microorganisms. In vitro studies show that beverages with pH below 5.5 are able to cause demineralization of the tooth surface. The Ministry of Agriculture Livestock and Supply (MAPA) provides the manufacture of guarana soda with acidity greater than or equal to 0.1 g of citric acid per 100ml. For quantification of acidity in soft drinks the potentiometric methods are indicated, as for determining the acidity of colored samples, which can not see the turning point when using chemical indicators. The aim of this study was to analyze the acidity of guarana soda. The samples were obtained in trade Cuité-PB and subsequently submitted to descabonatação in ultrasound for 90 minutes. In a beaker was added 40 mL of degassed sample, under stirring and inserted an electrode for pH readings. The potentiometric titration was carried out with 0.05N NaOH solution, where each 0.5 ml of NaOH added, the pH was recorded value, until the solution reached one pH de value 9.00. From the data mathematical equations have been applied to find the equivalence point, which occurs when the amount of titrant added equals the amount of acid present in the sample. This technique proved to be simple, accurate and inexpensive. The results show that the samples analyzed lie within the determined acidity limits by Brazilian law to guarana soda and there was uniformity of production between lots of brand A (face), how the brand B (cheap) They showed small differences between the values of acidity. All influence the cause of dental erosion.