Postharvest Behavior of Two Peach Varieties During Cold Storage and Shelf Life: Physiological and Sensory Perspectives

The postharvest behavior of two peach varieties (Pavía Canario and Moscato Tardío) was evaluated during 30 days of refrigerated storage at 0 °C followed by 5 days at 20 °C (shelf life). Firmness, respiratory activity, sugar content, total polyphenol content (TPC), total antioxidant capacity (TAC; ferric reducing antioxidant power, FRAP; 2,2-diphenyl-1-picrylhydrazyl, DPPH; and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), ABTS), and sensory attributes were assayed. Respiratory activity peaked around day 15 in both varieties, with Moscato Tardío showing higher values than Pavía Canario, reflecting differences in cold stress response. During refrigerated storage, Moscato Tardío maintained higher firmness (36.1 N) than Pavía Canario (27.2 N), although firmness decreased by ~30% after transfer to shelf life. Glucose and sucrose contents were higher in Moscato Tardío, while Pavía Canario showed higher initial TAC (FRAP: 117.2 mg ascorbic acid equivalents AAE·kg^-1; DPPH: 472.8 mg AAE·kg^-1). TPC increased over time in both varieties, but with different dynamics: Pavía Canario peaked at 20 days, whereas Moscato Tardío increased markedly at 30 days. ABTS values varied intra-varietally, showing maximum differences during storage. Sensory evaluation indicated better juiciness and reduced mealiness in Moscato Tardío throughout storage and shelf life. Overall, postharvest responses were genotype-dependent: Pavía Canario activated antioxidant defenses earlier, while Moscato Tardío exhibited delayed but substantial responses, maintaining firmness and sugar content, and better overall sensory quality.