Effect of loading speed on tensile texture of apple peels

Stress damage, such as cracking, fragmentation, and swelling of the peel seriously impact the quality and economic value of the fruit. Red Fuji and Danxia apple peels were selected to investigate the relationship between stress damage and chemical composition. The effects of 8 loading speeds during the tensile texture of apple peel were compared in terms of fracture morphology. The tensile strength and elastic modulus of Danxia peel reached the maximum values (2.51 ± 0.25 and 22.74 ± 3.77 MPa) at 1 and 2 mm/s, respectively, while Red Fuji peels reached maximum values (2.26 ± 0.29 MPa) at 0.1 mm/s. At the same loading speed, the tensile strength and the fracture strain of Danxia peel were significantly different from that of Red Fuji peel ([Formula: see text]). For both varieties, the peel fracture surface was wavy and linear, and the peel texture showed viscoelasticity with tear resistance. The cellulose and hemicellulose content of Danxia peels were significantly higher than those of Red Fuji peels ([Formula: see text]). The cellulose and hemicellulose content were related to the tensile strength values, while the elastic modulus was closely related to the pectin content.