Effect of Drying Methods on Volatile Compounds of Burdock (Arctium lappa L.) Root Tea as Revealed by Gas Chromatography Mass Spectrometry-Based Metabolomics

Abstract

Burdock (Arctium lappa L.) is one of the nutritional foods widely planted in many countries. Dried burdock root (BR) is available as a herbal tincture and tea in many Asian countries with good flavor and taste. In this study, the volatile components in dried BR were identified and the effects of different drying methods on the volatile components were investigated by HS-GC-MS method. A total of 49 compounds were identified. Different drying methods including hot-air drying (HD, at 50, 60, 70, and 80 °C), vacuum drying (VD, at 50, 60, 70, and 80 °C), sunlight drying (SD), natural drying (ND), and vacuum freeze drying (VFD) were evaluated by HS-GC-MS-based metabolomics method. Results showed that different drying methods produced different effects on the volatile compounds. It was observed that 2,3-pentanedione, 1-(1H-pyrrol-2-yl)-ethanone, furfural, and heptanal were detected at higher concentrations in HD 80 and VD 70. The traditional HD and SD methods produced more flavor substances than VFD. The BR treated by the VFD method could maintain the shape of the fresh BR pieces while HD50 and VD80 methods could maintain the color of fresh BR pieces. These findings could help better understand the flavor of the corresponding processed BR and provide a guide for the drying and processing of BR tea.

Effect of Yellowing Duration on the Chemical Profile of Yellow Tea and the Associations with Sensory Traits

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Aloe vera Gel Drying by Refractance Window®: Drying Kinetics and High-Quality Retention

“…Over 85% of industrial food dryers are convective, with mostly hot air as the media for heat transfer; often resulting in significant levels of changes in product quality from the initial fresh-like form [ 17 ]. Along with food quality retention, energy efficiency is equally important in the drying process, which is why both aspects are the subject of intensive research and development on food science [ 18 , 19 , 20 , 21 ]. Among the technologies currently deployed for the drying of valuable products, freeze-drying is very expensive, and despite the high-quality of its products, its use is limited to high-value products [ 15 , 18 , 22 ].…”

Effect of Freeze-Thaw Cycles on Juice Properties, Volatile Compounds and Hot-Air Drying Kinetics of Blueberry

“…The volatile compounds were analyzed according to a previous study [16]. An Agilent 7890B-5977B gas chromatograph-mass spectrometer equipped with an Agilent 7697A Headspace auto-sampler (Santa Clara, CA, USA) was used.…”