effect of calcium chloride concentration on some mechanical properties of apple during storage

today, the use of coatings is common to maintain the quality of fruits in storage period. previous studies have shown that the calcium compounds can improve and preserve the strength of fruit’s cell wall. in this research, the effect of calcium chloride dehydrate (cacl2*2h2o) concentration on two varieties of apple (golden delicious and red delicious), was studied. the apples were immersed in the calcium chloride dihydrate solution and then transferred to a cold storage. the effect of three concentration levels: 0, 3 and 6 percent, and three storage durations: no storage, one month and two months, were investigated on the apples mechanical properties such as failure stress, failure strain, modulus of elasticity and toughness. statistical factorial experiments in the form of completely randomized design were used to analyze the obtained results. the anova results showed that the effect of calcium chloride concentration was significant on the modulus of elasticity (p<0.05) and the yield stress (p<0.01), but is not significant on the toughness and the yield strain. the average yield stress at 0, 3 and 6% cacl2 concentration levels were 178, 183 and 193 kpa, respectively. comparison of means with duncan test showed a significant increase (p<0.01) for all concentration levels on the yield stress of apple tissue. the effect of storage duration was significant on the modulus of elasticity, the yield stress and the yield strain (p<0.01) and the toughness (p<0.05). also the effect of variety was significant for all the mechanical properties .none of the interaction effects, i.e. variety × concentration, variety × storage and concentration × variety on the modulus of elasticity and the toughness were significant.