桂热2号红茶冷冻干燥关键技术研究及品质评价  

Research on freeze-drying key technology and quality evaluation of Guire2 black tea

作　　者：阳景阳 罗莲凤 骆妍妃 陈远权 李子平 冯红钰 覃宏宇 韦锦坚 YANG Jingyang;LUO Lianfeng;LUO Yanfei;CHEN Yuanquan;LI Ziping;FENG Hongyu;QIN Hongyu;WEI Jinjian(Guangxi South Subtropical Agricultural Science Research Institute,Chongzuo 532415,China)

机构地区：[1]广西南亚热带农业科学研究所,广西崇左532415

出　　处：《食品与发酵工业》2021年第20期97-104,共8页Food and Fermentation Industries

基　　金：崇左市科技计划项目(崇科攻2020003);广西茶叶产业科技先锋队专项(桂农科盟202006-1);广西农科院科技发展基金(桂农科2020YM146)。

摘　　要：鉴定分析冷冻干燥、热风干燥桂热2号红茶香气成分及内含物差异,探索冷冻干燥关键工艺参数对红茶品质的影响。采用固相微萃取-气质联用(solid phase micro-extraction/gas chromatography-mass spectrometry,SPME/GC-MS)技术鉴定不同干燥处理红茶的香气成分,气味活度值(odor activity value,OAV)法评价香气成分贡献度,确定关键风味组分;结合感官审评、香气评价和内含物差异分析,对桂热2号红茶进行综合评价。共鉴定出37种香气成分,咖啡因、芳樟醇、水杨酸甲酯、苯乙醇、苯甲醇等成分相对含量较高;芳樟醇为关键风味组分(OAV>1),2-甲基丁醛、异丁醛、香叶醇、苯乙醛、二甲基硫、水杨酸甲酯等为修饰性风味组分(0.1<OAV<1);冷冻干燥处理能较大程度保留红茶的水浸出物、茶多酚、儿茶素等内含物质,并且在外形、汤色和易泡性上优于热风干燥处理,但在香气评价、节约成本上稍差。GC-MS结合OAV法能实现红茶香气的鉴别与评价;烘干+提香工艺红茶(HD2)综合评价最好;该研究的一种冷冻干燥+提香工艺(FD4)解决了冻干红茶青味重的问题,可运用于特色红茶加工。The aim of this study was to identify and analyze the difference in aroma components and contents of freeze-dried and hot-air-dried Guire2 black tea,and explore the influence of key processing parameters of freeze-dried black tea on quality.The aroma components extracted with solid phase microextraction(SPME)were identified by gas chromatography-mass spectrometry(GC-MS).And odor activity value(OAV)was used to evaluate the contribution of aroma components and determine the key flavor components.Combined with sensory evaluation,aroma evaluation and inclusion difference analysis,Guire2 black tea was evaluated comprehensively.A total of 37 aroma components were identified,which including a relatively high content of caffeine,linalool,methyl salicylate,phenyl ethanol and benzyl alcohol.Linalool was the key flavor component(OAV>1),and 2-methyl-butaldehyde,iso-butaldehyde,geraniol,phenylacetaldehyde,dimethyl sulfide,and methyl salicylate were the modified flavor components(0.1<OAV<1).Moreover,the freezing-drying treatment could retain the water extract,tea polyphenols,catechin and other contents of black tea to a large extent,and was superior to the hot-air drying treatment in appearance,liquor color and brewing simplicity,but slightly inferior in aroma evaluation and cost-saving.GC-MS combined with OAV could realize the identification and evaluation of black tea aroma.The comprehensive evaluation of hot-air-drying plus aroma-improving black tea(HD2)was the best.In this study,a freeze-drying plus aroma-improving process(FD4)solved the problem of the heavy grass flavor of the freeze-dried black tea and had advantages in appearance,brewing simplicity and retention of the contained nutrients,which can be used in the processing of characteristic black tea.

关 键 词：桂热2号红茶 冷冻干燥技术 香气成分 气味活度值 儿茶素 

分 类 号：TS272.52[农业科学—茶叶生产加工] O657.63[轻工技术与工程—农产品加工及贮藏工程]