The effect of cold storage time on some physiological properties of two apple cultivars

Different biological and environmental factors، harvesting way، transport، storage time and the method of storage are affected agricultural product properties. As a result of climacteric nature and continuous physiological life of apple fruit، the biochemical changes are very economic. This study was designed for obtain deep knowledge from this changes and effects of them in apple quality. In first week of Oct. 2012 the fruits of two apple cultivars harvested and stored in cold house (Malekan city، East Azarbaijan). Independently factors، storage time (0، 45، 90، 135 days) and cultivar (Golden delicious and Red delicious)، were tested with factorial analysis in completely randomized design for some apple fruit characteristics. Results showed significant differences between cultivars in most biochemical characteristics. With increasing storage time، protein، soluble sugars، reducing and non-reducing sugars contents and the juice pH were significantly increased; however، titratable acidity، total soluble solids and electrical conductivity were decreased. Cold storage did not significant change on insoluble sugars content. It is assumed that time dependent biochemical changes may occur with cold storage of apple fruits hence leads to changing the quality of fruits.