Mild heat treatments before minimal processing reduce browning susceptibility and increase total phenolic content of low‐chill apple cultivars

Three low-chill apple cultivars ("Caricia," "Eva," and "Princesa") were subjected to hot water treatments as a postharvest abiotic stress for quality retention. The effects of heating time and temperature, storage time, and apple cultivar were investigated on total phenolic content (TPC), firmness, color and polyphenol oxidase (PPO), and peroxidase (POD) activities. Apples were heat treated in water at 40–50°C for 20–90 min, stored at 2°C during 24 hr, and minimally processed. Samples were analyzed immediately and after 7 days at 2°C. Apple cultivar and storage time significantly affected the evaluated attributes. Heat treatments did not improve the firmness, color, or TPC of "Caricia" and "Princesa." While in "Eva" heat treatments increased TPC by 70%, reduced PPO and POD activities and prevented browning development, after 7 days. In conclusion, mild heat treatments could improve the quality and bioactive compound content of low-chill fresh-cut apples. Nevertheless, the different responses among cultivars should be accounted for. Practical applications The three low-chill apple cultivars, "Caricia," "Eva," and "Princesa," showed varying responses toward postharvest heat treatment. The TPC of the three studied cultivars was increased by the heat treatment at the minimal processing day. The application of mild heat treatments before minimal processing proved to be an effective postharvest tool to delay enzymatic browning and increase TPC of fresh-cut "Eva" apples, after 7 days of cold storage.