Estabilidade de ácido ascórbico em sucos de maracujá, acerola e suas combinaçöes, näo pasteurizados, armazenados a 4§C / Ascorbic acid stability in non pasteurized fruit juices of passion fruit, acerola and their combination, stored at 4§C

ABSTRACT

Ascorbic acid stability was studies in passion fruit, acerola and mixtures of these fruit juices, non pasteurized, vacuum packed but not deaerated, stored under refrigeration for 30 days. Initial amount of ascorbic acid in acerola juice was 1787.1 mg/100g and in passion fruit 26.5 mg/100g juice. The calculated value for vitamin C content for the mixed juices was higher than the determined value, showing an antagonist model for the combination. After the storage period passion fruit juice retained 29.5 per cent, acerola 73.4 per cent and the various proportion mixtures retained, on the average, 90.7 per cent of the initial content of ascorbic acid. Degradation rate constant was 4.2x10-2 day -1 for passion fruit juice and 14.8 mg/day for acerola juice. The combination juices had reduction in vitamin C too low to be evaluated kinetically