Postharvest hot air treatment effects on the antioxidant system in stored mature-green tomatoes

'Rhapsody' tomatoes were exposed to air at 20 (control), 34 or 38 degrees C, and 95% RH for 24 h and then stored at 4 degrees C or 20 degrees C for up to 4 weeks. Fruit exposed to 34 or 38 degrees C and stored at 20 degrees C had higher cysteine, '' reduced glutathione '', catalase, and glutathione S-transferase, but lower isoascorbic acid and ascorbate peroxidase compared to control fruit. Fruit exposed to 38 degrees C developed slight heat injury, and had slightly lower beta-carotene, lycopene, cysteine, ascorbate peroxidase, catalase, and '' reduced glutathione '' compared to fruit exposed to 34 degrees C. Fruit stored at 4 degrees C had less color development, lower beta-carotene, lycopene, ascorbic acid, isoascorbic acid, dehydroascorbic acid, cysteine and '' reduced glutathione '', and higher alpha-tocopherol, dehydroascorbate reductase, peroxidase, catalase, and glutathione reductase than those stored at 20 degrees C. Of the two heat treatments, 34 degrees C for 24 h caused little injury, and had less negative effects on antioxidants during storage at 4 or 20 degrees C than did prior exposure to 38 degrees C. (c) 2006 Elsevier B.V. All rights reserved.