تاثیر تاریخ برداشت و غلظت کلرورکلسیم بر کیفیت انبارمانی گلابی ارقام اسپادونا و کوشیا

Abstract
Harvesting date of pear cvs. "Spadona" and "Coscia" and the effect of different CaCl2 concentrations on fruit quality in cold storage were studied. The experimental design was structured as factorial with 4 factors and 3 replicates based on completely randomized design. Pear cv. " Coscia " was harvested in July 24th, July 31st and August 6th and " Spadona" in August 7th, August 14th and August 21st. After treatment with CaCl2 solutions (0, 4% and 6%), the fruits were transferred to cold storage (at 0 - 1 º C, 85-90% RH) and preserved for 6 months. The qualitative characteristics of fruits were calcium content, total soluble solids, titrable acidity, TSS/TA, reduced sugar and flesh firmness. They were measured immediately after harvesting and after 30, 60, 90, 120, 135, 150, 165 and 180 days stored in cold storage. At the end of storage time, sensory attributes (texture, color, taste, odor and overall quality) were determined. Results revealed that flesh firmness of cv. Coscia was higher (1.3 lb/in2) but cv. Spadona has higher total soluble solids and TSS/TA. Besides the scores of texture, color, odor and overall quality were higher in cv. Spadona. The results showed that pear cv. Spadona that was harvested in August 21st (heat unit=1986/8, full bloom=140 days) and treated with 6% CaCl2 solution, had highest calcium content and gained the highest score of panelist for overall quality. Totally this treatment maintained the best qualitative and quantitative characteristics and sensory attributes after 180 storing days in cold storage.

Keywords: Pear cultivars, Harvesting date, CaCl2 solutions, Calcium content, Overall quality