Effect of post-harvest calcium application on quality and shelf life of rippen strawberry fruit

Strawberry is one of the main agricultural products in Kordestan province. Because of it&rsquos tenderness and lack of possibilities for processing , 30 –40 percent of fruits would be wasted during the transportation between harvest to consumption . So,developing the shelf life of this fruit is important . One of the recommended ways for declining the wastes of harvested fruits is the application of calcium salts after harvest stage to increase the concentration of Ca2+ in fruit tissues. For this reason , the selected fruits were treated by immersing in 0 ,25 ,50 and 75 mmol/lit concentrations of CaSo4 , CaCl2 and Ca(No3)2 for 5 min. The first concentration (0) was assumed as control sample. After drying in atmospheric tempetature , fruits were stored at 3°C for 5 and 10 days . To evaluate the effect of calcium solutions on fruit quality , some quantitative and qualitative tests were carried out . The results showed that when the concentration of calcium salts is being increased , the amount of acidity , calcium and vitamin C of fruits is increased significantly , but the percentage of mouldy fruits is decreased . In most cases , the 50 and 75 mmol /lit concentrations of CaSo4 showed similar effects . Among the different calcium solutions , Ca(No3)2 had the best effect on improvement of fruit quality, such as increasing the vitamin C , calcium and hardness of fruit , but CaSo4 prohibited the mouldness of fruits better than other solutions . By increasing the period of storage from 5 to 10 days , the amount of acidity , hardness and vitamin C decreased significantly , while mouldness percentage increased. The organoleptic test showed that when the concentration of CaCl2 and Ca(No3)2 solutions is increased , the acceptability of treated samples is decreased by consumers. Because of the bitter taste, the least score was given to the samples treated by 75 mmol/lit concentration of Ca (No3)2 solution. The panelists didn&rsquot recognize any difference between control and samples which treated by 25 mmol/lit concentration of CaSo4 and CaCl2 solutions . None of the treatments , showed initial attributes of fruits such as tenderness , shape and color after storage period .