Effect of CaCl_2 and Exogenous Putrescine on Post-harvest Life and Quality of Peach (Prunus persica (L.) Batsch) Fruit, cv.' J. H. Hale'

摘要

The effect of 40, 60 and 80 mM calcium chloride (CaCl_2 ) and 0.5, 1 and 2 mM putrescine (Put) on post-harvest life and quality of peach (Prunus persica L. cv. 'J. H. Hale') fruit was studied. This experiment was carried out by immersing fruits in solutions at 25°C for 5 min, then transferring them into storage at 1-2°C and 75% relative humidity, together with untreated fruits (dry) as well as fruits immersed in distilled water only. Ethylene production, soluble solids content (SSC), titratable acidity (TA), pH, flesh firmness, weight loss and ascorbic acid (AA) of fruits were measured at regular intervals (5 days for cold storage and 2 days for shelf life) throughout the experiment. Quality of fruits was also tested through a taste panel at the end of experiment. During the whole storage time in which 5 measurements were performed, 60 mM CaCl_2 was the best treatment for keeping fruit quality in terms of flesh firmness, SSC, AA, TA, pH and weight loss. The highest score in terms of fruit quality, as given by panelists, corresponded to 60 mM CaCl_2 and 2 mM Put. Among the Put solutions, 2 mM could maintain the quality of fruits preventing ethylene production at the highest rate compared to other treatments. The results of a microbiological testshowed that 80 mM CaCl_2 was the best treatment to control yeast and mold populations significantly (P < 0.05). Put solutions were better than CaCl_2 treatments in terms of preventing ethylene production by fruits. Lower quality fruit was observed when fruit was immersed in distilled water only.