Effects of storage duration and conditions on mechanical properties of Viola cucumber fruit under compression loading

Abstract

In this research, the effects of storage duration and storage conditions on mechanical properties of cucumber fruit (Viola variety) were evaluated at different positions of the fruit length.  The cucumber fruit mechanical properties determined in this study were firmness, apparent modulus of elasticity, failure stress, failure strain and failure energy.  The mechanical properties determined under compression loading using puncture and uni-axial compression tests.  The results showed that the storage duration, storage conditions and fruit test position had significant (P<0.01) effect on the mechanical properties of Viola cucumber fruit.  The samples firmness, modulus of elasticity, failure stress and failure energy reduced about 49%, 39%, 38% and 33%, respectively during shelf life.  The failure strain of samples increased 18% during storage time.  Changing the mechanical properties of the cucumber fruit at room conditions was faster than refrigerator conditions.  The mechanical properties were differed along the length of cucumber fruits so that near the stem region of cucumber fruit had the maximum value of firmness, modulus of elasticity, failure stress and failure energy.  The sample failure strain had the minimum value at near the stem region of cucumber fruit.  Among the mechanical parameters that were evaluated in this research work, the firmness can be considered as the most appropriate parameter to evaluate textural properties of Viola cucumber fruit due to significant effect of independent parameters on it and ease of usage.