Determination of Sutaible Harvesting Time and Its Effect on Postharvest Kiwifruit Quality

The harvest date more influenced on postharvest quality during storage. In present study, fruits were harvested at four date base on total soluble solids content (5.5, 6.5, 7.5, and 8.5%) and then stored at 0.5 ºC and 80-90% RH, for 18 weeks. The samples were taken in 6th, 12th and 18th interval weeks and evaluated some parameters including weightless, losses, firmness, TSS, TA, TSS/TA, ascorbic acid, pH, EC, Skin and pulp lightness and sensory analysis. Results showed that different harvesting time had not significant effect on wieghtloss and pH parameters during storage. Also, we observed that fruits which were harvested at brix of 5.5 had high firmness specialy during primery 6 weeks storage. The skin of fruits picked with 5.5 and 6.5 % brix was a little darker than other treatments. EC showed reverse relationship with storage period during storage. With TSS increasing, TA level decreased during storage. Although, ascorbic acid content was higher during 6 weeks of storage but it was lower in fruits which picked with 5.5 % brix than other times of harvest. Finally sensory analysis revealed that fruits which harvested at least 6.5 oBrix content, would have excellent quality after storage and handling.