EVALUATION OF THE SYNERGISTIC ACTIVITY BETWEEN CHITOSAN FROM SQUID PLUME (DOSIDICUS GIGAS) AND CITRIC ACID IN THE BROWNING OF CUSTARD APPLE PULP (Annona cherimola Mill.)

Abstract

The research study consisted of three stages: firstly, obtaining and characterizing the chitosan extracted from the squid plume, secondly selecting the appropriate variety of custard apple based on the yield of the fruit, and thirdly, studying the synergistic effect between chitosan and citric acid on control of enzymatic browning of custard apple pulp. In the characterization of the chitosan a value of 846 kDa of molecular weight and 78.2% of the degree of deacetylation was obtained. Using a Completely Randomized Design (CRD), three cherimoya varieties (Lisa, Impresa and Umbonata) were evaluated, selecting the Lisa variety for the highest pulp yield; then a Completely Randomized Block Design (CRBD) was used evaluating four
treatments (T) in triplicate in the standardized pulp, the fourth treatment (0.75% chitosan + 3% citric acid) presented the lowest polyphenoloxidase activity (70,80 PPO units/ min xg of sample) and slowed the oxidation of the total polyphenol content (28 mg of gallic acid/100 g by weight of fresh pulp) during the evaluation. The projection of useful life in the pulp was obtained using the Arrhenius equation and the color variation, with the fourth treatment presenting the longest time (254 days), evidence of a synergistic effect that contributes to delaying the enzymatic browning in the pulp of the custard apple.