عنوان مقاله [English]
Background: Long shelf life is considered as an economically important feature for the kiwifruit. Several factors are involved in maintaining the quality of kiwifruit during storage that Among them harvest time and nutrient elements can be named. Harvest time and nutrient elements such as calcium has impressive effects on maintenance of fruit quality in storage. In this study effect of harvest time on kiwifruit quality during storage, the amount of calcium and potassium fruit tissue and the correlation of these elements with fruit quality characteristics were studied.
Material and method: The experiment was conducted as a factorial experiment in a completely randomized design. Fruits used in this study from two cultivars Abbot and Hayward in two different harvest times with 9 and 12 degrees Brix were collected and refrigerated at a temperature of 5°C and a relative humidity of 70% for 4 months. Changes in quality of fruits using chemical and physical variables were measured monthly and the results were analyzed by SAS 9 statistical software.
Results: The results showed that harvest time with 12 °Brix had higher quality in the amount of phenolic compounds, antioxidant capacity and vitamin C. Firmness, total soluble solid and vitamin C decreased during storage, but the decline was slower in 12 °Brix at harvest time and this process in Hayward was slower than Abbot cultivar. According to the results of the correlation study, Ca had significant positive correlation In probability level of 5% with TSS and antioxidant capacity and In probability level 1% with flavor index. K had significant positive correlation In probability level of 5% with Titratable Acidity and significant negative correlation In probability level 1% with Total Soulble Solid and antioxidant capacity. Harvested fruits in 12ºBrix indicated a higher calcium and lower potassium showing better quality of fruit.
Conclusion: Kiwifruit harvested in the area of study (Kordkoy) in the second harvest due to higher levels of calcium and lower potassium of fruit texture had higher fruit quality characteristics during storage. The Abbot compared to Hayward cultivar for both of the applied harvest time. In this respect, Abott cultivar had lower calcium content in fruit texture which showed lower storage potential in comparison with Hayward cultivar. as a result to achieve optimal fruit quality during storage in addition to maturity level, cultivar and the nutrient element contents of the fruit also may be monitored.
Keywords: Correlation, kiwifruit, nutrient elements analysis, storage, Soluble Solids Content.