Influence of ripening on the ethylene and carbon dioxide production during storage of plum fruits

摘要

The fruits of 13 plum cultivars were analysed at two different stages of maturity: first when they were ready for picking according to conventional commercial criteria, and again after seven days of maturation at 20 °C in a normal oxygen atmosphere during shelf life. Firmness, soluble solids concentration (SSC), respiration rate and the production of ethylene were measured. In the period of over-ripening SSC increased, and no differences were found in relation to the cultivar. The fruits in this period were physiologically in a phase of reduced intensity of respiration, while production of ethylene increased and was associated with the earliness of the cultivar. Cultivars with a short vegetation period produce more ethylene while late-maturing cultivars have a low potential for ethylene production. Based on post-harvest changes in the tested quality factors, the late-ripening plum cultivars (cv.) ‘Jojo’, ‘Topend’, ‘President’, ‘Tophit’ and ‘Elena’ have higher storage potential. Changes in ethylene production in response to shelf life seem to play a regulatory role in fruit firmness. A high significant negative correlation was detected between levels of skin firmness and ethylene production.