Impact of drying methods on physicochemical properties of Fritillaria hupehensis (Hubeibeimu) flours

Abstract

Fritillaria hupehensis (Hubeibeimu) widely grows in the mid-western zones of China. In the present work, we investigated the physicochemical compositions, antioxidant abilities, and thermal properties of the bulbs of F. hupehensis dehydrated by heat-pump drying (HD), vacuum drying (VD), natural drying (ND), freeze drying (FD), and microwave drying (MD). Total contents of nucleosides and nucleobases in F. hupehensis flours ranged from 727.64 to 1,654.25 μg/g, and total free amino acids ranged from 88.03 to 128.21 mg/g. FD flour had high contents of total nucleosides and nucleobases, and free amino acids. MD flour had low contents of total starch, amylose, protein, nucleosides and nucleobases, and VB1 and VB2, and high levels of total phenolic content (TPC) and antioxidant abilities. Furthermore, MD flour facilitated gelatinisation, while FD flour displayed opposite trend. HD flour had high total starch content, while ND flour weakened the bitter taste due to the percentage of sweet and bitter taste of amino acids.