Selection of drying technology based on dynamic effects on physicochemical properties and flavours of mulberry

Abstract

: Mulberry is gaining attention for its potential health benefits. However, post-harvest deterioration of quality necessitates drying to prolong storage. This study aimed to investigate the effects of natural drying (ND), hot air drying (HAD), and vacuum freeze drying (VFD) on bioactive compounds and volatile organic compounds of fresh mulberries. The results showed that VFD had the highest retention of total phenols (5 553.87 ± 744.97 µg GAE·g –1 ) (GAE – gallic acid equivalent), total flavonoids (3 575.51 ± 465.98 µg rutin·g –1 ), and total anthocyanins (64.98 ± 13.15 µg C3C·g –1 ) after prolonged drying. Additionally, flavour was identified as the most important indicator influencing consumer preference for dried mulberries, and VFD was found to be effective in retaining the natural flavours of mulberries. Although thermal treatment leads to a significant loss of organic compounds, HAD showed good retention of active substances and lower energy consumption in a shorter processing time.