The influence of drying methods on the physicochemical, functional, and antioxidant properties of passion fruit peel

oleh: LIU Zhaohan, YANG Tongxiang, XU Hanshan, LI Xuejing, CHEN Junliang, REN Guangyue, DUAN Xu

Format: Article
Diterbitkan: ZHU Beiwei 2023-12-01

Deskripsi

<b>Objective:</b> This study aimed to investigate the effects of drying methods on passion fruit peels. <b>Methods:</b> Passion fruit peels were treated with microwave vacuum freeze-drying, vacuum freeze-drying, heat pump drying, and far-infrared radiation drying. The drying characteristics, rehydration ratio, color difference, dietary fiber, functional properties, microstructure, total phenolic content, total flavonoid content, and antioxidant properties were measured and determined respectively. <b>Results:</b> Heat pump-dried passion fruit peels had poor rehydration ratio and functional properties. Microwave vacuum freeze drying reduced the drying time by 53% when compared tp far-infrared radiation drying, and the microwave vacuum freeze-dried treated passion fruit peels had a higher rehydration ratio (7.45), total phenolic content (13.45 mg GAE/g DW) and antioxidant activity (DPPH was 38.53%, FRAP was 1.14 mmol/L). Additionally, the passion fruit peels were vacuum freeze-dried with treatment to increase their water holding capacity [(21.64±0.21) g/g], oil holding capacity [(6.09±0.71) g/g], swelling [(25.00±1.00) g/g], and total flavonoid content (7.84 mg RT/g DW). Different drying techniques led to higher rehydration ratios, and they also significantly differed (<i>P</i><0.05) in terms of dietary fiber, functional properties, total phenolic content, total flavonoid content and antioxidant activity of the peels. <b>Conclusion:</b> The quality of passion fruit peel can be greatly affected by the drying process, and microwave vacuum freeze-drying is the most preferred technique.