Study on fruit harvest time and preharvest environmental conditions on Kiwifruit (Actinidia deliciosa cv Hayward) storage time.

Fuzzy kiwifruit (Actinidia deliciosa cultivar Hayward ) are now produced commercially worldwide, with the largest planted areas in Iran. It is a perennial vine with deciduous fruits and belong to Actinidiaceae family. Fruit quality after post harvest was so affected by harvest time in Hayward kiwifruit. The objectives of this project were to determine the effects of harvest maturity, climate, and storage conditions on subsequent fruit quality of Actinidia deliciosa Hayward . The influences of location (west and centeral of Mazandaran province), harvest maturity (5.5, 6.5, 7.5, and 8.5% average total soluble solids content (TSS)) and storage conditions (0.5 ºC and 80-90% RH, or 2 °C and 88% RH for 18 weeks) on the physicochemical and sensory qualities of Hayward kiwifruit were investigated. The samples had taken in 6th, 12th and 18th weeks and water loss, firmness, TSS, TA, TSS/ TA, vitamin C, pH, EC, Skin and pulp color index (L*, a*, b* and chroma) and sensory analysis of fruits were evaluated. Results showed that all fruits had lowest water loss both two years experimental, specially at the first sampling (after 6 weeks). The samples had taken from west of Mazandaran showed peak of firmness both two years particularly samples which harvested at 5.5 oBrix content. No more significant differences were observed between all treatments about L*, b* and chroma of skin and L* of pulp characteristics but pulp chroma value improved in west fruits. Fruit TSS content was highest (16.14%) in those of that harvested at 7.5 oBrix content after 18 weeks dealing in storage. Fruits harvested at 8.5 oBrix content from central and west location had high levels of TA with 1.69 and 1.59 % respectively. EC showed reverse relationship with during of storage. Vitamin C content was uppermost in fruits which harvested at 6.5 oBrix content from middle (first year) as well as those harvested at more than 6.5 oBrix, that were well maintained in secondary year. Finally sensory analysis revealed that fruits which harvested at least 6.5 oBrix content, would have excellent quality after storage and handling.