Drying Characteristics and Quality Analysis of Jasmine with Combined Microwave and Hot Air Drying

Abstract

In this paper, the effects of three kinds of microwave (MVD, 1.5, 2.0, 2.5 min) and hot air (HAD) drying at 60 ℃ on the drying characteristics and quality of jasmine were compared and analyzed. The results showed that in microwave drying stage, the water content of jasmine decreased rapidly, which accelerated the moisture decline in jasmine in hot air drying stage. The water-soluble extract, hydroxyl radical inhibitory ability, total amino acid and essential amino acid content of jasmine flower dried by combined microwave and hot air drying were higher than those of HAD group. The color and peak area of total volatile components, benzyl alcohol and α-fendene and of jasmine flowers in MVD2.0+HAD and MVD2.5+HAD groups were higher than those in HAD, which indicated that the typical fragrance of jasmine dried by MVD1.5+HAD and MVD2.0+HAD could be better retained. The difference of volatile components of jasmine dried by combined microwave and hot air drying could be distinguished by LDA analysis in electronic nose. In conclusion, jasmine dried by MVD2.0+HAD had the best quality.

Keywords

• jasmine
• combined microwave and hot air drying
• drying characteristics
• quality analysis