ABSTRACT Several studies have used edible packaging for food preservation due to its composition of biodegradable polymers and natural additives. In the present work, bioactive extracts obtained from the fermented and unfermented flour of tamarind residues were incorporated into formulations of edible coatings for the conservation of grapes of the cultivar ‘Italia’. The flours extracts were obtained with 80% aqueous ethanol solution. Edible coating formulations containing 10 g L-1 cassava starch and 5 g L-1 chitosan without extract or containing 10 g L-1 unfermented or fermented flour extract were prepared and applied to grapes stored at 25 °C for 15 days. The physical-chemical characteristics of the coated and uncoated fruits were similar during storage. The addition of fermented and unfermented flour extracts to the edible coatings improved the in vitro antioxidant activity of the grapes, especially that determined by the ferric reducing antioxidant power method, on the last day of storage, with emphasis on grapes coated with a formulation containing fermented residue extract. Extracts of tamarind residues incorporated in edible coatings promoted the acquisition of bioactive coatings with the potential to improve the antioxidant activity of grapes during 15 days of storage at 25 °C.

Abstract Fruit residues (peel, seed, and pulp residues) have in their composition several compounds such as polyphenols, carotenoids, fibres, and lipids which, due to their functional properties, these compounds make them potential sources of natural additives. The great technological challenge is to use the most suitable techniques for extracting these compounds. In this paper, definitions, advantages, and disadvantages of conventional (maceration, soxhlet extraction, hydrodistillation) and emerging (Ultrasonic-Assisted Extraction (UAE), Microwave-Assisted Extraction (MAE), Supercritical Fluid Extraction (SFE), Pressurized Liquid Extraction (PLE), and Pulsed Electric Field (PEF)) techniques for the extraction of bioactive compounds from fruit residues will be shown. Some emerging techniques are based on non-thermal process, reduced use of energy and the implementation of no toxic solvents, being considered “green” or “clean” technologies. These ones are particularly interesting to extract heat-labile compounds. In addition, enzyme-assisted extraction and extractions through fermentation processes (submerged or solid-state fermentation) will be highlighted as alternative to promote the release of compounds from fruit residues not extracted by other techniques. These extractions techniques can enhance the content of bioactive compounds by increased their concentrations, as well as new compounds can be formed after these processes. It has been proven that the emerging techniques and fermentative processes, as alternative to conventional methods, are promising to extract bioactive compounds from fruit residues, since that these techniques improved extraction yields, reduced processing times, and reduced environmental damage are achieved.

Abstract The mango has short postharvest shelf life which varies from 6 to 10 days at room temperature in its fresh form. The objective of this study was to evaluate the effect of usage of edible coatings based of cassava starch and chitosan on post-harvest shelf life of mango. Mangoes of Tommy Atkins variety were covered with nine different formulations of coatings in a factorial block experimental design. The fruits were stored at 25 °C and evaluated during storage for the weight loss (%), color parameters, sensory attributes evaluated by trained panel, the rate of CO2 production and microbiological contamination on the peels. Results analysed by linear regressions and ANOVA, demonstrated that chitosan showed significant effect on weight loss (%) and on values of L*, a*, b*, chroma, ºhue, peel color, texture, aroma and time which correlated well for suitability of fruit consumption. The formulation containing 0.25% of chitosan and 0.5% of cassava starch showed most favorable results as it presented a post-harvest shelf life of 3 days more than the control fruits and lower rates of CO2 production, showing that this coating actually decreased the rate of the respiratory processes of mango, without compromising the proper ripening of the fruit.