Effects of Different Drying Methods on the Sensory Quality and Physical and Chemical Properties of Apple-peach Flat Leather

To investigate the impact of various drying methods on the sensory quality and physical and chemical properties of apple-peach flat leather, five drying methods (hot air drying, oven drying, microwave drying, oven-hot air combined drying and oven-microwave combined drying) were used to prepare apple-peach flat leather. The differences in sensory evaluation, texture, color, browning degree, content of total phenol and vitamin C and antioxidant activity of apple-peach flat leather prepared by different drying methods were investigated. Hot air-dried products were found to be more attractive to sensory assessors in terms of taste, color, and flavor. Furthermore, they received the highest sensory rating score (86.7), the highest total phenolic content (5.66 mg GAE/g dw), strong antioxidant activity (DPPH free radical clearance rate was 66%, the total reducing capacity of FRAP was 0.32 mmol Trolox/g dw), but the vitamin C content was lower (4.56 mg/100 g) and the browning degree was higher. Microwave dried apple-peach flat leather had the highest vitamin C content (9.78 mg/100 g), but the lowest sensory evaluation score was 66.7, total phenol content (4.11 mg GAE/g dw) and the lowest antioxidant activity (DPPH free radical scavenging rate was 58%, The total reduction capacity of FRAP was 0.18 mmol Trolox/g dw). There were no distinguishing features in the products by oven-hot air combined drying and oven-microwave combined drying. According to the findings of the study, microwave oven drying was not advised for the manufacturing of apple-peach flat leather, but hot air drying could be used instead.