Metabolic response to combined mild heat pre-treatments and modified atmosphere packaging on fresh-cut peach.

摘要

The combined influence of mild heat pre-treatments (MHPT) and 2 types of modified atmosphere packaging conditions on metabolic responses of fresh-cut peaches was monitored during an 8-day refrigerated (4degC) period. Quality parameters evaluated included solute leakage, wt. loss, firmness, colour, pH, soluble solids content, respiration rate, activities of polyphenol oxidase (catechol oxidase) and pectin methylesterase (pectinesterase) and concn. of vitamins, organic acids and sugars. Lower levels of malic acid were observed in heat-treated samples, whereas succinic and citric acids were not affected. Provitamin A (beta-carotene) was not affected by MHPT. Decreases in ascorbic acid contents during storage were similar in both treated and untreated samples. Significant firmness improvements occurred after MHPT, due to the activation of pectin methylesterase and the ensuing production of calcium pectates. The passive modified atmosphere was able to preserve the quality of fresh-cut peaches subjected to MHPT.