Browning evaluation of ready-to-eat apples as affected by modified atmosphere packaging

Abstract

The color and polyphenol oxidase (PPO) activity of fresh-cut Golden delicious apples were evaluated throughout cold storage under modified atmospheres. The shelf life of cut apples was extended to several weeks, especially when an initial atmosphere of 90.5% N2 + 7% CO2 + 2.5% O2 and plastic pouches of 30 cm3/cm2·bar·24 h were used. Under these conditions, a maximum 62% PPO activity depletion was observed. In all cases, the faster the initial PPO activity decays, the less the color changes. A fractional conversion first-order model was proposed for predicting color changes in minimally processed apples. Browning was better described through lightness (L*) (kL = 0.017 − 0.07 day-1) and color difference (ΔE*) values (kΔE = 0.015 − 0.073 day-1), which fitted the model with enough accuracy.