基于感官组学分析不同足火方式对金牡丹工夫红茶香气的影响

doi:10.13305/j.cnki.jts.2023.01.010

摘要/Abstract

摘要： 为探究不同足火方式对红茶香气的影响,以金牡丹茶树秋季鲜叶为原料,使用高温热风（80 ℃）、低温热风（40 ℃）、脱水热风（热泵）、真空冷冻4种干燥方式加工工夫红茶,采用顶空固相微萃取（Headspace solid-phase microextraction,HS-SPME）结合气相色谱-质谱联用（Gas chromatography-mass spectrometry,GC-MS）、气相色谱-嗅辨联用（Gas chromatography-olfactometry,GC-O）、香气活度值（Odor activity value,OAV）、香气特征影响值（Aroma character impact value,ACI）以及香气审评方法,比较不同干燥方式工夫红茶关键香气化合物种类、含量及其对香气的贡献程度。结果表明,4种干燥方式红茶在香型、香气化合物的种类与含量等方面均存在显著差异。香气审评表明,高温干燥红茶呈现不愉悦的闷味,低温干燥红茶花香不显且青草气较重,热泵干燥红茶呈现清爽的花香,冷冻干燥红茶香气协调,花果香保留好且青气不显。GC-MS结果表明,4-戊烯醛、1-辛烯-3-酮、(E)-3-己烯-1-醇乙酸酯等物质仅在高温干燥工夫红茶中检出,是高温干燥红茶闷味的来源;低温干燥红茶中由OAV及GC-O判定为活性香气成分的呈花香的芳樟醇及其氧化物含量显著较低,呈青草气的(Z)-2-戊烯醇等挥发性成分含量显著高于传统高温干燥工夫红茶,热泵干燥红茶中由OAV及GC-O判定为活性香气成分的呈花果香的芳樟醇及其氧化物、苯甲醛、苯乙醛、水杨酸甲酯、香叶醇,以及呈青草气的(Z)-2-戊烯醇等含量与贡献度均高于其他干燥方式红茶;冷冻干燥红茶中上述香气物质含量及比例均衡。正交偏最小二乘判别分析（Orthogonal partial least squares discrimination analysis,OPLS-DA）和拟合预测变量投影重要性（Variable importance in projection,VIP）结果表明,OPLS-DA模型可靠且筛选出19种VIP值高于1的化合物。研究结果表明,热泵及冷冻干燥技术均能有效减少传统高温足干工艺所产生的闷味,可用于提高红茶花果香气品质。该研究可为红茶加工中香气品质的提升及工艺选择提供技术参考和理论指导。

关键词: 红茶, 香气, 干燥方式, 气相色谱-质谱联用, 气相色谱-嗅辨联用

Abstract: To investigate the effect of different full firing methods on the aroma of black tea, four full firing methods, namely high temperature (80 ℃), low temperature (40 ℃), dehydrated hot air (heat pump) and vacuum freezing, were used to process Congou black tea samples using the fresh autumn tea leaves of ‘Jinmudan’. The samples were analyzed by gas chromatography-mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O), odor activity value (OAV), aroma character impact value (ACI) and aroma evaluation methods were used to compare the types and contents of key aroma compounds and their contribution to the aroma of black tea by different full firing methods. The results show that there were significant differences between the four full firing methods in terms of aroma type, classes and content of aroma compounds. The results of aroma evaluation show that: high temperature dried black tea showed an unpleasant sulky odor. Low temperature dried black tea showed no floral odor and a heavy grassy odor. Heat pump dried black tea showed a refreshing floral odor. Vacuum freezing dried black tea showed a harmonious odor with good retention of floral and fruit odor and no grassy odor. The contents of linalool and its oxides, which were determined as active aroma components by OAV and GC-O, were significantly lower in low temperature full-fired black tea. While the contents of active aromas such as (Z)-2-pentenol, which present a grassy aroma, were significantly higher than that of traditional high temperature full-fired black tea, and the contents of linalool and its oxides, benzaldehyde, phenylacetaldehyde, methyl salicylate, geraniol, etc., which show floral and fruit aromas in heat pump full-fired black tea, were significantly higher than that of traditional high-temperature full-fired black tea. The contents and contribution of linalool and its oxides, benzaldehyde, benzylaldehyde, methyl salicylate, geraniol and (Z)-2-pentenol, which show floral and fruity aromas, were higher in black tea full-fired by heat pump than in black tea full-fired by other full firing methods. The results of orthogonal partial least squares discriminant analysis (OPLS-DA) and variable importance in projection (VIP) show that the OPLS-DA model was reliable and 19 compounds with VIP value higher than 1 were screened. The results show that both heat pump and freeze-drying technologies can effectively reduce the sulky aroma of traditional high temperature full firing processes and can be used to improve the floral and fruit aroma of black tea. This study provided a technical reference and theoretical guidance for the improvement of aroma quality in black tea and process selection in processing practice.

Key words: black tea, aroma, drying method, GC-MS, GC-O

中图分类号:

魏昊, 蓝天梦, 缪伊雯, 孟庆, 坤吉瑞, 张玉, 童华荣. 基于感官组学分析不同足火方式对金牡丹工夫红茶香气的影响[J]. 茶叶科学, 2023, 43(1): 109-123. doi: 10.13305/j.cnki.jts.2023.01.010.

WEI Hao, LAN Tianmeng, MIAO Yiwen, MENG Qing, KUN Jirui, ZHANG Yu, TONG Huarong. Analysis of the Effect of Different Full Firing Methods on the Aroma of Jinmudan Congou Black Tea Based on Sensomics Characterization[J]. Journal of Tea Science, 2023, 43(1): 109-123. doi: 10.13305/j.cnki.jts.2023.01.010.

参考文献

[1] Zhang L, Ho C T, Zhou J, et al.Chemistry and biological activities of processed Camellia sinensis teas: a comprehensive review[J]. Comprehensive Reviews in Food Science and Food Safety, 2019, 18(5): 1474-1495.
[2] 喻洁瑶. 冲泡条件和特征性挥发物对祁门红茶品质的影响[D]. 重庆: 西南大学, 2021.
Yu J Y.Effect of brewing conditions and characteristic aroma compounds on the quality of Keemun black tea [D]. Chongqing: Southwest University, 2021.
[3] 谢关华, 陆安霞, 欧阳珂, 等. GC-MS 结合化学计量学用于探究六大茶类香气形成的差异[J]. 食品与发酵工业, 2021, 47(20): 260-270.
Xie G H, Lu A X, Ouyang K, et al.Analysis of the aroma formation in six categories of teas by GC-MS combined with chemometrics[J]. Food and Fermentation Industries, 2021, 47(20): 260-270.
[4] Bokuchava M A, Skobeleva N I, Sanderson G W.The biochemistry and technology of tea manufacture[J]. Critical Reviews in Food Science & Nutrition, 1980, 12(4): 303-370.
[5] Lin X Y, Zhang L J, Lei H W, et al.Effect of drying technologies on quality of green tea[J]. International Agricultural Engineering Journal, 2010, 19(3): 30-37.
[6] Bhatta S, Stevanovic Janezic T, Ratti C.Freeze-drying of plant-based foods[J]. Foods, 2020, 9(1): 87. doi: 10.3390/foods9010087.
[7] Chua K J, Chou S K, Yang W M.et al.Advances in heat pump systems: a review[J]. Applied Energy, 2010, 87(12): 3611-3624.
[8] 滑金杰, 王华杰, 王近近, 等. 采用PLS-DA分析毛火方式对工夫红茶品质的影响[J]. 农业工程学报, 2020, 36(8): 260-270.
Hua J J, Wang H J, Wang J J, et al.Influences of first-drying methods on the quality of congou black tea using partial least squares-discrimination analysis[J]. Transactions of the Chinese Society of Agricultural Engineering, 2020, 36(8): 260-270.
[9] Ye F, Qiao X Y, Gui A H, et al.Metabolomics provides a novel interpretation of the changes in main compounds during black tea processing through different drying methods[J]. Molecules, 2021, 26(21): 6739. doi: 10.3390/molecules26216739.
[10] 崔继来. 糖苷类香气前体对乌龙茶和红茶香气形成的贡献[D]. 重庆: 西南大学, 2016.
Cui J Y.Contribution of glycosidically bound volatiles on the aroma formation of oolong tea and black tea [D]. Chongqing: Southwest University, 2016.
[11] 冯红钰, 刘汉焱, 梁光志, 等. 茶树良种金牡丹试制性研究[J]. 中国热带农业, 2013(3): 49-50.
Feng H Y, Liu H Y, Liang G Z, et al.Study on trial production of tea cultivar Jinmudan[J]. China Tropical Agriculture, 2013(3): 49-50.
[12] Zhu B Y, Zhang J, Li J Y, et al.Aroma profile of Jinmudan tea produced using Camellia sinensis, cultivar Jinmudan using solid-phase microextraction, gas chromatography-mass spectrometry, and chemometrics[J]. European Food Research and Technology, 2021, 247: 1061-1082.
[13] Li J Y, Hao C H, Jia H Y, et al.Aroma characterization and their changes during the processing of black teas from the cultivar, Camellia sinensis (L.) O. Kuntze cv. Jinmudan[J]. Journal of Food Composition and Analysis, 2022, 108: 104449. doi: 10.1016/j.jfca.2022.104449.
[14] 中华全国供销合作总社. 茶叶感官审评方法:GB/T 23776—2018[S]. 北京: 中国标准出版社, 2018.
All China Federation of Supply and Marketing Cooperatives. Methodology for sensory evaluation of tea: GB/T 23776—2018 [S]. Beijing: China Standard Press, 2018.
[15] Liao X L, Yan J N, Wang B, et al.Identification of key odorants responsible for cooked corn-like aroma of green teas made by tea cultivar ‘Zhonghuang 1’[J]. Food Research International, 2020, 136: 109355. doi: 10.1016/j.foodres.2020.109355.
[16] Van Den Dool H, Dec. Kratz P. A generalization of the retention index system including linear temperature programmed gas-liquid partition chromatography[J]. Journal of Chromatography A, 1963, 11: 463-471.
[17] Shimoda M, Shigematsu H, Shiratsychi H, et al.Comparison of the odor concentrates by SDE and adsorptive column method from green tea infusion[J]. Journal of Agricultural and Food Chemistry, 1995, 43(6):1616-1620.
[18] Wang B, Meng Q, Xiao L, et al.Characterization of aroma compounds of Pu-erh ripen tea using solvent assisted flavor evaporation coupled with gas chromatography-mass spectrometry and gas chromatography-olfactometry[J]. Food Science and Human Wellness, 2022, 11(3): 618-626.
[19] Lee S M, Chung S J, Lee O H, et al.Development of sample preparation, presentation procedure and sensory descriptive analysis of green tea[J]. Journal of Sensory Studies, 2008, 23(4): 450-467.
[20] 肖作兵, 王红玲, 牛云蔚, 等. 基于OAV和AEDA对工夫红茶的PLSR分析[J]. 食品科学, 2018, 39(10): 242-249.
Xiao Z B, Wang H L, Niu Y W, et al.Analysis of aroma components in four Chinese congou black teas by odor active values and aroma extract dilution analysis coupled with partial least squares regression[J]. Food Science, 2018, 39(10): 242-249.
[21] 徐奕鼎, 丁勇, 黄建琴, 等. 祁门红茶初制中的干燥工艺研究[J]. 中国农学通报, 2013, 29(27): 204-209.
Xu Y D, Ding Y, Huang J Q, et al.Studies on drying process at primary processing of keemun black tea[J]. Chinese Agricultural Science Bulletin, 2013, 29(27): 204-209.
[22] 王梦琪, 朱荫, 张悦, 等. 茶叶挥发性成分中关键呈香成分研究进展[J]. 食品科学, 2019, 40(23): 341-349.
Wang M Q, Zhu Y, Zhang Y, et al.A review of recent research on key aroma compounds in tea[J]. Food Science, 2019, 40(23): 341-349.
[23] Wang C, Li J, Wu X J, et al.Pu-erh tea unique aroma: Volatile components, evaluation methods and metabolic mechanism of key odor-active compounds[J]. Trends in Food Science & Technology, 2022, 124: 25-37.
[24] Mao S H, Lu C Q, Li M F, et al.Identification of key aromatic compounds in Congou black tea by partial least-square regression with variable importance of projection scores and gas chromatography-mass spectrometry
/gas chromatography-olfactometry[J]. Journal of the Science of Food and Agriculture, 2018, 98(14): 5278-5286.
[25] 宛晓春. 红、绿茶干燥过程的热化学变化[J]. 茶叶科学, 1988, 8(2): 47-52.
Wan X C.Thermochemical changes of black tea and green tea during drying[J]. Journal of Tea Science, 1988, 8(2): 47-52.
[26] Qu F F, Qiu F F, Zhu X J, et al.Effect of different drying methods on the sensory quality and chemical components of black tea[J]. LWT-Food Science and Technology, 2018, 99: 112-118.
[27] Feng Z H, Li M, Li Y F, et al.Characterization of the key aroma compounds in infusions of four white teas by the sensomics approach[J]. European Food Research and Technology, 2022, 248(5): 1299-1309.
[28] Ma L J, Gao M M, Zhang L Q, et al.Characterization of the key aroma-active compounds in high-grade Dianhong tea using GC-MS and GC-O combined with sensory-directed flavor analysis[J]. Food Chemistry, 2022, 378: 132058. doi: 10.1016/j.foodchem.2022.132058.
[29] Yang Y Q, Zhu H K, Chen J Y, et al.Characterization of the key aroma compounds in black teas with different aroma types by using gas chromatography electronic nose, gas chromatography-ion mobility spectrometry, and odor activity value analysis[J]. LWT-Food Science and Technology, 2022, 163: 113492. doi: 10.1016/j.lwt.2022.113492.
[30] Xu Q L, Pan H J, Shui Y R, et al.Effect of different drying technologies on the characteristics and quality of lemon slices[J]. Journal of Food Science, 2022, 87(7): 2980-2998.
[31] Kumazawa K, Masuda H.Identification of potent odorants in different green tea varieties using flavor dilution technique[J]. Journal of Agricultural and Food Chemistry, 2002, 50: 5660-5663.
[32] Yun J, Cui C J, Zhang S H, et al.Use of headspace GC/MS combined with chemometric analysis to identify the geographic origins of black tea[J]. Food Chemistry, 2021, 360: 130033. doi: 10.1016/j.foodchem.2021.130033.
[33] 汪蓓, 舒娜, 陆安霞, 等. 不同杀青温度对绿茶香型形成的影响[J]. 食品与发酵工业, 2020, 46(4): 197-203.
Wang B, Shu N, Lu A X, et al.Aroma formation of green tea effected by different pan-fire temperature[J]. Food and Fermentation Industries, 2020, 46(4): 197-203.
[34] 苏振晖. 浦城县金牡丹红茶加工技术[J]. 现代农业科技, 2014(20): 272, 279.
Su Z H. Pucheng county Jinmudan black tea processing technology [J]. Modern Agricultural Science and Technology, 2014(20): 272, 279.
[35] Nie C N, Gao Y, Du X, et al.Characterization of the effect of cis-3-hexen-1-ol on green tea aroma[J]. Scientific Reports, 2020, 10: 15506. doi: 10.1038/s41598-020-72495-5.
[36] 赵升云, 张见明, 黄毅彪, 等. 武夷岩茶热泵干燥工艺的试验研究[J]. 海峡科学, 2018(5): 40-43, 47.
Zhao S Y, Zhang J M, Huang Y B, et al.Experimental study on heat pump drying process of Wuyi rock tea[J]. Straits Science, 2018(5): 40-43, 47.
[37] Ma C H, Tan C, Li W L, et al.Identification of the different aroma compounds between conventional and freeze dried Wuyi rock tea (Dangui) using headspace solid phase microextraction[J]. Food Science and Technology Research, 2013, 19(5): 805-811.
[1] 阳景阳, 罗莲凤, 骆妍妃, 等. 桂热2号红茶冷冻干燥关键技术研究及品质评价[J]. 食品与发酵工业, 2021, 47(20): 97-104.
Yang J Y, Luo L F, Luo Y F, et al.Research on freeze-drying key technology and quality evaluation of Guire2 black tea[J]. Food and Fermentation Industries, 2021, 47(20): 97-104.