S. Moradi - Department of Horticultural Science, University of Kurdistan, Sanandaj, Islamic Republic of Iran.
Ma. Koushesh Saba - Department of Horticultural Science, University of Kurdistan, Sanandaj, Islamic Republic of Iran.
A. A. Mozafari - Horticultural Science Research Institute, Temperate Fruits Research Center, Agricultural Research Education and Extension Organization (AREEO), Karaj, Islamic Republic of Iran.
H. Abdollahi - Horticultural Science Research Institute, Temperate Fruits Research Center, Agricultural Research Education and Extension Organization (AREEO), Karaj, Islamic Republic of Iran.

Quince fruit has many benefits to human health and is an excellent source of pectin for jellies and jam industry. The objective of the present research was to study fruit physio-chemical attributes of some quince genotypes at harvest and their changes during cold storage. The fruit of ۱۵ genotypes were harvested at optimum maturity and stored for ۰, ۳۰, ۶۰, ۹۰ and ۱۲۰ days in cold storage and some parameters were measured. The range of ۱۳.۰۰-۱۸.۷۶% for Soluble Solid Content (SSC), ۰.۳۸-۰.۹۵% for titratable acidity, ۲.۵۵-۳.۷۵ for pH, ۵۲.۱۶-۹۱.۰۰ N for firmness, ۰.۸۹-۰.۹۸ g cm-۳ for density, ۲۵۵.۳۹-۳۴۹.۵۶ mg ۱۰۰ g-۱ DM for carbohydrate, ۷.۲۸-۲۳.۰۲% for pectin and ۱۱.۶۶-۳۳.۳۰% for fruit fibers were observed across genotypes at harvest time. Negative correlations were found between weight loss and both firmness and density, while firmness had positive correlation with pectin and Ca content. Generally, significant changes (P≤ ۰.۰۵) for measured characters were observed across genotypes and during cold storage, but the rate of changes varied according to genotypes. It was found that each studied genotype had one or more unique character such as lowest weight loss in ‘Paveh ۱’, highest fruit firmness retaining in ‘Marivan۱’, highest pectin in ‘Marivan ۱’ and highest SSC in ‘Marivan ۲’, that are promising for fruit breeding in future programs.

Firmness, fruit quality, Pectin, Postharvest