effect of postharvest oxalic acid and calcium chloride on quality attributes of sweet cherry (prunus avium l.)

introduction: fruits and vegetables have special importance as a very important part of the human food supply. and from the beginnings of life, man has used these products to supply a part of his food. nowadays, horticultural products are widely used in the diet. cherry is one of the deciduous trees in the temperate regions, which is potassium rich. use of oxalic acid significantly reduces frost injury in pomegranate fruits during storage at a temperature of 2° c. in fruit trees, the importance of calcium is due to a delay in fruit ripening process and this way products have better portability. materials and methods: firmness test was measured using the ft011 model of penetrometer. for determination of titratable acidity, the 0.1 n sodium hydroxide (naoh) titration method was used. total soluble solids content (ssc) of fruit was measured by a digital refractometer (pal-1). for determination of vitamin c in fruit juices, titration method with the indicator, 2,6-di-chlorophenolindophenol was used. fruit juice ph was measured using ph meter model hi 9811.in order to investigate the effect of postharvest soaking treatment with oxalic acid on the qualitative specifications and storage life of single grain sweet cherry fruit a research was conducted. this experience was conducted in a completely randomized design with 3 replications separately for the two materials. in this experiment oxalic acid, in four levels (0,4,6 and 8 mm) and calcium chloride in four levels (0, 40, 55 and 70 mm) were applied on the single grain sweet cherry fruit in the form of soaking and sampleswith7-day intervals for a period of 28 days from the fridge out and quanti tate and qualitative traits such as stiffness, weight loss, titratable acidity, total soluble solids, vitamin c and ph were measured. results and discussion: the results showed that compared with control ones all of the concentrations of oxalic acid and calcium chloride caused significant differences in the amount of weight loss, firmness, acidity, tss, vitamin c and ph , so that weight loss rate on the fourth week for control samples was 39/79%, for samples treated with 8mm oxalic acid, 22/77%, and for 70 mm calcium chloride, 21/19%; total soluble solids weight on the fourth week for control samples was 24/53%; for samples treated with 8mm oxalic acid 21/43% and for 70 mm calcium chloride 21/13%; and vitamin c weight on the fourth week for control samples was 2/65; for samples treated with 8mm oxalic acid 3/06 and for 70 mm calcium chloride 3/16; also firmness and acidity were more than that of control. conclusion:in fruits treated with different concentrations of calcium chloride, the amounts of firmness, acidity and vitamin c were significantly higher than that of control. also in treated fruits, the amounts of weight loss, total soluble solids and ph during storage were significantly lower than that of control. in fruits treated with different concentrations of oxalic acid in fruits, the amounts of firmness, acidity and vitamin c were significantly higher than that of control. and in fruits treated with different concentrations of oxalic acid, the amounts of weight loss, total soluble solids and ph were significantly lower than that of control. according to the results of this test calcium chloride treatment was better when compared with oxalic acid.