physical and biochemical changes of some iranian quince (cydonia oblonga mill) genotypes during cold storage

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 15 genotypes were harvested at optimum maturity and stored for 0, 30, 60, 90 and 120 days in cold storage and some parameters were measured. the range of 13.00-18.76% for soluble solid content (ssc), 0.38-0.95% for titratable acidity, 2.55-3.75 for ph, 52.16-91.00 n for firmness, 0.89-0.98 g cm-3 for density, 255.39-349.56 mg 100 g-1 dm for carbohydrate, 7.28-23.02% for pectin and 11.66-33.30% 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≤ 0.05) 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 1’, highest fruit firmness retaining in ‘marivan1’, highest pectin in ‘marivan 1’ and highest ssc in ‘marivan 2’, that are promising for fruit breeding in future programs.