Abstract: The influence of hot air drying, microwave drying, freeze drying, heat pump drying and vacuum drying on the physical properties and bioactive components of germinated highland barley were studied. The results indicated that the comprehensive score was the highest by freeze drying, and the contents of total flavonoids, γ-aminobutyric acid, β-glucan, total phenols and riboflavin the germinated highland barley were (3.21±0.11)mg/g, (7.51±0.20)mg/g, (4.90±0.16)%, (3.08±0.32)mg/g and (2.24±0.014)g respectively. At the same time, it also retained the complete cell structure and the smallest volume shrinkage rate of (7.75±1.11)%. Microwave drying had higher drying rate, but its total contents of flavonoids, γ-aminobutyric acid and β-glucan were reduced by 18.28%, 64.13% and 37.00% compared to that of freeze drying, and it had the lowest comprehensive score (-0.333). The comprehensive scores of hot air drying, heat pump drying and vacuum drying were lower, the scores were -0.219, -0.052 and -0.212, respectively. And the loss of bioactive ingredients of heat pump drying was relatively low. In view of the low cost and high efficiency of heat pump drying, it can be used to germinated highland barley in actual production.
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