The effect of hot water, 1-MCP, and lovastatin on fresh-cut apples after long-term controlled atmosphere storage

Authors: MEHMET ALİ KOYUNCU

Abstract: This research was carried out over two years to determine the quality changes in fresh-cut apple slices processed after hot water, 1-methylcyclopropene (1-MCP), and lovastatin treatments followed by controlled atmosphere (CA) storage. Apples harvested at the optimum stage were immediately transferred to the postharvest laboratory by a refrigerated vehicle. Intact apples were exposed to three treatments: dipping into hot water (50 °C for 60 s), treating with lovastatin (1.25 mmol L^-1), and treating with 1-MCP (1 µL L^-1). Treated apples and the control group were stored in CA storage (2% O2 + 2% CO₂ ) for 10 months. After long-term storage, the apples, sliced and packaged in plastic boxes, were stored at 0 °C and 90 ± 5% relative humidity (RH) for 14 days. Weight loss, soluble solid content, flesh firmness and color, titratable acidity, respiration rate, microbial count, and ethylene synthesis were determined during storage. As a result, a global beneficial effect of 1-MCP on sliced apples was observed, although its affirmative effect on ethylene synthesis and respiration rate vanished after 10 months of storage. 1-MCP-treated slices had better results in terms of microbial count, flesh firmness, external appearance, and weight loss compared to other applications. Lovastatin decreased the ethylene synthesis and respiration rate and was the best treatment to maintain the flavor of apple slices. Hot water and control treatments gave similar results for fruit quality and microbial activity. After long-term cold storage (10 months) in CA, fresh-cut apple slices could be stored for 7 days with good quality at 0 °C and 90 ± 5% RH.

Keywords: Minimal processing, microbial activity, quality, postharvest treatments, Granny Smith

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