Métodos para minimizar perdas de qualidade de acerola e jabuticaba: Imersão em CaCl2, congelamento e liofilização

Abstract

Acerola and jabuticaba were chosen for this study because they are seasonal fruits, have similar sizes, large production in Brazil, perishables and due to the need to apply conservation methods to prolong post-harvest quality. In addition, it is known that some fruits are consumed with their skin, such as acerola, and others without their skin, such as jabuticaba. Therefore, the objective of this work was to observe the effect of the freezing rate (slow and fast), evaluating some characteristics of acerola (representing fruits consumed with peel) and jabuticaba (representing fruits consumed without peel), using different treatments. Acerola and jabuticaba were submitted to treatments by infusion in calcium chloride, freezing at different temperatures (slow freezing in freezer and fast freezing in ultrafreezer) and lyophilization. Physicochemical, colorimetric, scanning electron microscopy (SEM), rheological behavior (jabuticaba) and perforation resistance (firmness) were performed. According to the results, for acerola, the infusion in CaCl2 did not interfere in the analyses, except for the microstructure, slow freezing caused greater damage to the fruit and the combination of fast freezing and lyophilization resulted in fruits with the most satisfactory quality. For jabuticaba, CaCl2 changed significantly, only the microstructure, slow freezing, caused greater damage to the fruit; the best colorimetry results were for the combination of fast freezing and lyophilization; regarding the rheological behavior, the power law and the Hershell-Bulkley model showed the best fit, characterizing the frozen jabuticaba as a non-Newtonian pseudoplastic fluid.