Estabilidade de Yacon (Smallanthus sonchifolius) minimamente processado

Abstract

The present work had the objective of analyzing the stability of yacon minimally processed and submitted to different conservation methods, as well as to evaluate the effectiveness of these methods in the control of the enzymatic browning and to analyze the behavior of the physicochemical characteristics during the period of storage. The experiment was conducted in a completely randomized design with 3x4 factorial scheme, 3 treatments (Treatment 1: control sample, in natura; Treatment 2: Chemical whitening with 2 % citric acid solution for 15 minutes; and Treatment 3: Chemical whitening with 2 % citric acid solution for 15 minutes combined with the ultrasonic bath at 40 Hz / 10 minutes) and 4 evaluation periods (0, 3, 6, and 9 days of storage), with three replicates. The stability of the minimally processed yacon was evaluated by physicochemical analyzes of moisture, pH, total soluble solids and total titratable acidity. The control of the enzymatic darkening was evaluated through color analysis and enzymatic activity of polyphenoloxidase. The data were examined for the effect of time on the stability of the minimally processed yacon and on the efficacy of the methods in controlling enzymatic browning by means of analysis of variance (ANOVA), followed by comparison of the means by Scott-Knott at 5 % of probability. The color parameter indicated that the control treatment presented greater darkening than the other treatments, showing that the non-use of physical and / or chemical treatments made the production of yacon minimally processed unfeasible. The parameters moisture, total soluble solids and enzymatic activity of polyphenoloxidase did not present significant difference between storage times for all treatments. Although ultrasound provides reduced enzymatic activity and color maintenance during storage, these effects were not significant in the present study. Many of the results obtained in the parameters analyzed in the ultrasonic assisted chemical treatment resemble those obtained with the chemical treatment. Through the obtained results, it can be concluded that the chemical and chemical treatments assisted by ultrasound provided greater stability to the minimally processed during the period of storage, presenting great viability of use.