Physiological maturity and wound-based orchard practices influence the antioxidant content and metabolic activity of two species of açai fruit at harvest and during storage.

Pre-harvest treatments like wound-based orchard management practices and early harvest were applied to açai plants (Euterpe oleracea Mart., Euterpe precatoria Mart.) to yield higher levels of antioxidants. Orchard practices like 50% shoot suppression and 50% cluster thinning when applied 87 d before harvest (187 days DAA) were similar to control fruits at harvest and during storage (20 °C). However, lesions in the stipe applied 187 DAA altered the acid, carbohydrate, phenolic content and the ethylene biosynthesis compared to control fruits, showing enhanced fruit antioxidant activity. Early harvest of fruit including 120 and 150 DAA, showed higher acid, lower sugars, higher phenolic content and higher ethylene biosynthesis and respiration rate compared to control fruits, showing the highest levels of fruit antioxidant activity. The selected strategies studied may achieve higher yields of phenolic antioxdants from açai fruit and target high value health markets including functional foods and dietary supplements.

Nanomaterials as Alternative Control Means Against Postharvest Diseases in Fruit Crops.

Post-harvest diseases of fruit and vegetables have to be controlled because of the high added value of commodities and the great economic loss related to spoilage. Synthetic fungicides are the first choice worldwide to control post-harvest diseases of fruit and vegetables. However, several problems and constraints related to their use have forced scientists to develop alternatives control means to prevent post-harvest diseases. Physical and biological means, resistance inducers, and GRAS (generally recognized as safe) compounds are the most important alternatives used during the last 20 years. Recently, nanomaterial treatments have demonstrated promising results and they are being investigated to reduce the utilization of synthetic fungicides to control post-harvest rot in fruit and vegetables. The collective information in this review article covers a wide range of nanomaterials used to control post-harvest decays related to each selected fruit crop including grape, citrus, banana, apple, mango, peach, and nectarine. Other examples also used are apricot, guava, avocado, papaya, dragon, pear, longan, loquat, jujubes, and pomegranate fruits.