Avaliação físico-química e estabilidade do ácido ascórbico em sucos de frutas comercializados no município de Frutal, Minas Gerais

The objective was to analyzethe physical-chemical evaluation and the stability of ascorbic acid present in different brands of unpasteurized fruit juices and bottled in Tetra Pak packaging marketed in city of Frutal- Minas Gerais State. The objectives were to evaluate physical-chemical characteristics (pH, titratable acidity and total soluble solids in °Brix) and the stability of ascorbic acid by Tillmans method in fruit juices for a period of 21 days of storage under refrigeration. For this, the juices were purchased between May and June 2015, in the local market and then preserved in their containers until the time of analysis. According to the results obtained for the physical-chemical, pH, titration acidity and total soluble solids, showed variations during storage. However, most of the samples of juices meets the minimum quality parameters required by Ministry of Agriculture. The stability of ascorbic acid is found greater stability for orange juice (brand A and C) and passion fruit (brand B). Thus, it can be concluded that there was retention of ascorbic acid in fruit juices after 21 days of refrigerated storage, with possible minimization of losses of vitamin C during processing, indicating good quality of juices marketed in city of Frutal, Minas Gerais.