Effect of 1-MCP and low-temperature storage on postharvest conservation of camu-camu

Camu-camu, a native fruit from the Amazon region, is a rich source of bioactive compounds. However, its intense metabolic activity and high-water content limit the fruit's postharvest storage and marketing. The aim of this study, conducted in two parts, was to evaluate the effects of 1-MCP and storage temperature on the physiology and postharvest preservation of camu-camu fruit. In part 1 of the study, fruit harvested at maturity stage 3 were divided into groups: control, 1-methylcyclopropene (1-MCP; 900nL L-1; 12h) and ethylene (1000 mu L L-1; 24h) and were stored at 22 +/- 1 degrees C and 85 +/- 5% RH for 9days. In part 2, fruit harvested at maturity stage 3 were stored at 5, 10, 15, 20, or 25 +/- 1 degrees C and 85 +/- 5% RH for 9days. During storage, fruit were evaluated daily for decay, mass loss, respiratory activity, and ethylene production, and every 3days they were evaluated for peel color, pulp firmness, soluble solids content, total titratable acidity, ascorbic acid, total chlorophyll, and total anthocyanins. Fruit treated with 1-MCP exhibited delayed ripening due to lower metabolic activity, as evidenced by delay to softening, reduced mass loss and no decay. Storage at 5 degrees C prevented ethylene production, mass loss, color changes, and maintained pulp firmness, while did not affect soluble solids content. The results indicated that storage of camu-camu fruit at 5 degrees C or at 25 degrees C following application of 900nL L-1 1-MCP were effective strategies to delay ripening and maintain fruit quality up to 9days.