Volatile composition and quality of fresh-cut Cucumis melo var. Cantaloupensis and Inodorus as affected by modified and controlled atmospheres

Cantaloupensis melons are aromatic and fast senescing, whereas Inodorus have less odor and are slower senescing. Modified atmosphere packaging (MAP) is used to reduce respiration rate and extend shelf-life but may alter the synthesis of volatile compounds. We assessed the effects of passive MAP and controlled atmosphere (CA; 5 kPa O2 + 10 kPa CO2) upon quality and volatile production by fresh-cut 'Cantaloupe' and 'Honeydew' melons, stored at 5°C for 14 days. O2 concentration inside the MAP packages decreased during the 14 days, to 11.1 and 14.2 kPa, in 'Cantaloupe' and 'Honeydew', respectively. CO2 levels increased to 11.3 and 7.9 kPa during storage, for 'Cantaloupe' and 'Honeydew', respectively. In MAP, during the first 4 days of storage, cantaloupe cubes softened at a higher rate (2.0 N.day-1) than 'Honeydew' cubes (0.9 N.day-1). Conversely in CA, fresh-cut 'Honeydew' softened faster (1.9 N.day-1) than fresh-cut 'Cantaloupe' (0.9 N.day-1) which, softened faster between days 4 and 7 (2.1 N.day-1). Initial 'Cantaloupe' respiration was 17.5 ml CO2.kg-1.h-1, which increased to 63.8 and 43.4 ml CO2.kg-1.h-1 when stored in CA and MAP, respectively. Initial respiration of 'Honeydew' melon was 7.7 ml CO 2.kg-1.h-1, and increased to 55.5 and 30.0 ml CO2.kg-1.h-1 when stored in CA and MAP, respectively. Volatile compounds that are known to be flavorimportant in melons, were extracted using Stir Bar Sorptive Extraction (SBSE) and quantified via GC-MS. The production of acetate esters increased in both melons stored in MAP, but decreased in 'Cantaloupe' under CA conditions. Non-acetate esters increased in both cultivars and storage conditions. Alcohols, initially more abundant in 'Honeydew', underwent a decrease throughout storage. Aldehydes, initially more abundant in 'Cantaloupe', decreased in both melons for MAP but not in 'Honeydew' stored in CA. Lower O2 availability in fresh-cut fruit, stored under CA conditions utilized in this experiment, likely suppressed some of the acetate esters relevant to the aroma of fresh-cut melon.