TOMATO FLAVOR CHANGES AT CHILLING AND NON-CHILLING TEMPERATURES AS INFLUENCED BY CONTROLLED ATMOSPHERES

Postharvest temperatures recommended as safe to avoid chilling injury (CI) based on lack of visible symptoms suppress tomato aroma development. We investigated how temperatures at or above the putative CI threshold of 12.5°C affected aroma of pink ‘Tasti Lee’ tomatoes and if controlled atmosphere (CA) could overcome loss of shelf life at the higher temperatures without compromising aroma. Fruit were held for 10 days in air or CA. Aroma volatiles and other quality features were measured on days 0, 5, and 10 as well as after shelf life (2 days in air at 20°C). Fruit at 15 and 18°C ripened more uniformly during shelf life. 6-Methyl-5-hepten-2-one (MHO), a CI marker, increased at 18°C and was lowest at 12.5°C, and was also lower in CA than in air, even though its percentage of the total volatiles was higher in CA. Beta ionone, a volatile with very high log odor units, was also higher in air than in CA at all temperatures after D10. Geranyl acetone, which has a fruity aroma, and citral were higher at 18°C followed by 15 and 12.5°C on D10. Hexanal, a basic tomato aroma, increased over time at all temperatures. However, in CA its contribution as a percent of the total volatiles was higher than in air, indicating suppression of the other volatiles in CA. While CA reduced CI and extended shelf life, aroma was reduced, especially in more extreme CA, likely due to inhibition of ripening.