Desenvolvimento e caracterização de embalagem indicadora utilizando antocianinas a partir do extrato de Hibiscus sabdariffa

Abstract

The growth of the food packaging sector has driven the development of active and intelligent packaging capable of monitoring and extending food quality. In this context, the objective of this work was to develop and characterize collagen films incorporated with Hibiscus sabdariffa extract, evaluating their potential as pH-indicating packaging applied to ham. Water and ethanol were used as extraction solvents, for whole or macerated calyces, and the anthocyanin content was quantified by the pH differential method. The films were produced and characterized regarding their colorimetric response, antioxidant activity, and puncture resistance. The ethanolic extracts showed total anthocyanin contents close to 0.88 mg/g, almost twice the value obtained for the aqueous extract (0.48 mg/g). The films exhibited a visible colorimetric response to pH changes, evidenced by the gradual loss of the pink coloration throughout the ham incubation, following the pH increase resulting from the metabolic activity of spoilage bacteria. The antioxidant activity, evaluated by the DPPH method, showed that the films maintained higher and more stable inhibition percentages (35% to 51%) compared to the ham samples, which varied more inconsistently, even exhibiting pro-oxidant behavior when stored without refrigeration. The low compression resistance values of the developed materials demonstrate that the obtained material resembles a gel structure rather than a conventional plastic film. The presence of ethanolic extract, obtained without maceration of the calyces, resulted in a reinforcing effect at low concentrations and structural weakening at higher concentrations. It is concluded that the collagen film incorporated with hibiscus anthocyanins shows potential as active and freshness-indicating packaging for meat products, with refrigeration standing out as a determining factor for maintaining its antioxidant activity, although improvements in the formulation are necessary to enhance its mechanical resistance and structural stability.