Aroma formation in Dianhong black tea: Effects of baking

Abstract

Baking is the last, and yet most essential, step in the formation of the final distinct flavour of most black tea products. In this study, the influence of baking on the volatile components of Dianhong black tea, which is one of the most popular black teas in China, was investigated. As a very fast, effective, and simple method for collecting volatiles, headspace solid-phase microextraction (HS-SPME) with a 65 µm PDMS/DVB fibre was used to extract the volatile compounds of Dianhong black tea, and the volatile components were further separated and identified by gas chromatography-mass spectrometry (GC-MS). The results showed that the peak areas of alcohols, aldehydes, esters, and ketones were increased, but that those of some alkanes, acids, and nitrogen compounds did not demonstrate an obvious increase after baking. The differences generated by baking process actually result in the distinct flavour of most black teas and can be used as a model for analysing the chemical composition of special flavours, and for quality improvement and process control. ARTICLE HISTORY

Aroma Components Analysis and Origin Differentiation of Black Tea Based on ATD-GC-MS and E-Nose

“…The addition of β-glucosidase during black tea processing was found to increase the contents of the volatile monoterpene alcohol compounds, such as linalool and geraniol, in the black teas [38]. The Maillard reactions of tea leaves occurring during the drying process also increased the contents of linalool and its oxides, enhancing the aromas of the black teas [39]. Benzyl alcohol and phenylethyl alcohol were formed by the hydrolysis of benzyl β-D-glucoside with phenylethyl-β-Dglucopyranoside [38,40].…”

“…The addition of βglucosidase during black tea processing was found to increase the contents of the volatile monoterpene alcohol compounds, such as linalool and geraniol, in the black teas [38]. The Maillard reactions of tea leaves occurring during the drying process also increased the contents of linalool and its oxides, enhancing the aromas of the black teas [39]. Benzyl Since the flavour dilution factor is not a direct measure of the odour potency of the aroma compounds in foods, the odour activity values (OAVs), based on accurate quantitative data, are needed to assess the contributions of the flavour compounds [35].…”

Improvement of Antioxidant Activity and Sensory Quality of Pagilaran’s Tea Clones Treated by Tannase

“…This study showed that the tannase enzyme did not significantly affect odor because there were no changes in volatiles compounds. Qiu et al (2017) identified 53 volatile compounds in black tea with the HS-SPME (Head Space -Solid Phase Micro Extraction) extraction method. The most identified volatile compounds from alcohol groups were more than 70%, then aldehydes, hydrocarbons, ketones, and ester.…”

Effect of baking treatment on quality, nonvolatile and volatile compounds of Liupao tea

“…The taste of tea infusion and the sweetness of tea with baking are both improved by the addition of total soluble sugar (Mao et al ., 2018). Alcohols, aldehydes, and ketones, among other aroma compounds, diffuse to the surface of tea to create a pleasant odour that removes off‐flavours and enhances the aroma of tea (Qiu et al ., 2017). Therefore, baking is essential for enhancing the quality, consistency, type of aroma, and flavour of tea products.…”