USE OF FACTORIAL DESIGN METHODOLOGY IN FRUIT JUICE QUALITY RETENTION STUDIES

Abstract

Deterioration of fruit juice, an inherent problem that tends to impede the development of the fruit juice industry, is influenced by many variables in processing, handling, storage and distribution. Ascorbic acid is the least stable of all fruit juice nutrients, it is readily oxidized. Thus, its concentration is an index to the retention of the original nutritive value. The use of factorial design methodology in monitoring the degradation of ascorbic acid in fruit juices during ambient storage and distribution is presented in this work. The effects of storage temperature, brix value, pH, quantity of antioxidant  and duration of storage  on the ascorbic acid levels in orange, mango and pineapple juices, under non-refrigerated storage and distribution were investigated; optimal shelf-life and quality value models were developed. Data were drawn from a  full factorial experiments conducted in three replicates with the order of the replicate experiments randomized. Multivariate regression analysis was used for relating the variables. The optimal shelf-lives of the orange, and pineapple juices was 16 days and the respective values of ascorbic acid for this duration were 22.93mg\100ml, 25.89mg\100ml, and 11.69mg\100ml. The regression analysis model confirmed the mango juice model to be inadequate.