Tomato Fruit Chilling Tolerance in Relation to Internal Atmosphere after Return to Ambient Temperature

Abstract

Mature-green `Vedette' tomato (Lycopersicon esculentum Mill.) fruit were stored with (+P) or without (-P) peduncles at 1C. During storage and after return to ambient temperature, pigment content and electrolyte leakage of pericarp tissue and fruit internal atmosphere composition were monitored. The +P fruit showed severe chilling injury (CI) symptoms-shriveling and brown discoloration of the surface-on transfer to 20C after at least 8 days of exposure to low temperature. The chilling-injured fruit did not ripen normally; i.e., pigmentation did not change at 20C. The -P fruit were largely unaffected and ripened normally at 20C. Severely injured tomatoes showed an apparent decrease in electrolyte leakage after transfer to ambient temperature. The CO, content of the -P fruit internal atmosphere was significantly lower than in +P tomatoes after return to 20C. The peduncle scar has a greater permeability to gases than the skin and facilitates gas exchange with the external atmosphere. The accumulation of CO, in the internal atmosphere of the chilled +P fruit after transfer to 20C apparently promoted CI symptom development.