Determination of Relaxation Model for Apple (cv. Shafiabadi&Golabkohanz)

Abstract — The relaxation phenomena are critical aspects of fruit rheological properties. In this research, effects of variety and sampling orientation on stress relaxation model parameters (equilibrium stress, decay stress and relaxation time) of two Iranian apple varieties (ShafiAbadi & GolabKohanz) were investigated. Sampling was performed in horizontal and vertical orientation and the stress relaxation tests were performed using Instron Universal testing machine. The results showed that interaction effects of variety and sampling orientation on all of parameters were significant except for relaxation time. At the end, four stress relaxation models were presented.