五味子叶保健绿茶加工工艺比较研究

采用炒制杀青、蒸汽杀青和微波杀青3种不同方法处理五味子叶,干燥后制成五味子叶茶,测定毛茶感官指标和生化指标,研究不同加工工艺对五味子叶保健绿茶品质的影响,结果显示:与传统炒制杀青加工工艺相比,蒸汽杀青和微波杀青两种处理方法加工的五味子叶保健绿茶的品质感官指标综合得分在85分以上,其营养成分和药用成分溶出率也显著(p<0.05)提高。     

不同杀青温度对传统工艺六堡茶品质及成分的影响

以广西群体种茶树品系华江六垌茶的一芽二、三叶鲜叶为原料,研究了不同杀青温度对传统工艺六堡茶品质及内含成分的影响。结果表明：采用滚筒杀青时,杀青温度在220～240℃制作出来的传统工艺六堡茶品质较佳,干茶主要体现为香气纯正,汤色橙黄明亮,滋味浓醇、甘爽,叶底黄亮、匀整,同时干茶中含水量、水浸出物、茶多酚、咖啡碱、游离氨基酸的含量总体随着杀青温度的增加而逐渐减少,试验的结果有利于传统工艺六堡茶产品品质的提高。     

传统工艺“黄金六堡茶”加工关键技术参数研究

以2021、2022年创新研制茶叶鲜叶动态摊青槽(自制)试验加工的传统六堡茶为试验材料,进行感官、主要生化成分含量分析,对传统工艺六堡茶加工关键技术进行了梳理和总结。结果表明：以摊青时间6～8 h(在摊青至2 h和4 h时鲜叶分别做青1次每次5 min),杀青温度220±5℃,渥堆时间10～12 h,初烘90±5℃、足火100±5℃制得的传统工艺六堡茶汤色杏黄明亮、花蜜香浓郁、滋味醇厚,感官品质最好。通过研究,旨在探索传统工艺六堡茶加工关键控制技术,提高品质水平,并应用开发传统工艺“黄金六堡茶”茶叶新产品,对传统工艺六堡茶的发展具有积极意义。     

夏秋季绿茶加工工艺改良研究

在传统绿茶工艺的基础上增加了摊青和堆积工序,改锅式杀青为蒸汽杀青,并结合热揉等进行夏秋季绿茶加工工艺改良研究,初步确定了鄂北茶区夏秋季绿茶制作工艺流程为:摊青—蒸汽杀青—揉捻—初干—堆积—炒干。改良后的夏秋季绿茶品质与传统工艺相比有明显提高:综合品质比提高了11.0%,氨基酸含量、可溶性糖显著提高,茶多酚含量、酚氨比显著降低,苦涩味减轻。改良后的绿茶工艺各工序的主要技术参数为:摊青时间为3~5 h、摊青叶的含水量达70%左右、二青叶含水量40%左右、堆积时间2~3 h、炒干含水量4%~7%。     

茶树修剪时期和程度对早市名优茶品质的影响

本试验采取随机区组，就不同修剪时期和不同修剪深度对早市茶的品质影响作出了探讨。研究结果表明：不同修剪时期对茶多酚和氨基酸影响不显著，对可溶性糖影响较显著，而对水浸出物和叶绿素影响极显著；其中，以10月份轻修剪茶叶品质成分含量最高，早春2月份次之。在不同修剪程度方面，除了对氨基酸影响不显著外，对其它几种内质均极显著；茶叶主要内含成分的含量为未修剪＞轻修剪＞深修剪。从品质成分分析看，采摘茶园春茶前不修剪或10月份修剪有利于名优茶品质的提高。     

“雄州银毫茶”制作工艺

“雄州银毫茶”的品质特征：条索紧细卷曲，白毫披露隐翠，香气清高持久，滋味鲜醇甘爽，汤色清澈明亮，叶底嫩绿匀整。银毫条采制要求十分严格，采摘有三大特点：1、摘得早2、采得嫩3、拣得净。每年在清明前后开采，谷雨前后结束，历时20天左右，特级银毫鲜叶采摘标准为一芽一叶初展，芽长1．6至21厘米，细嫩的芽叶，加之优越的环境条件，为银毫菜优良品质形成提供了坚实的物质基础。银毫茶炒制的特点：手不离茶，茶不离锅，炒揉结合，读中带炒，炒中带揉，搓团显毫，精工细作。银毫茶制作工艺流程为：鲜叶采收——摊放轻萎凋——杀青——…     

关于银杏嫩叶手工制茶工艺的探讨

针对目前市场上银杏叶茶大多采用成熟叶作为原料加工而成,形、色、味等品质较差的现状,4月份采用3～4年生银杏幼树上的嫩叶作为原材料,运用鲜叶-杀青-揉捻-复炒-复揉-炒干加工工序,手工制作银杏嫩叶茶,从根本上改善、提高银杏叶茶品质。     

机制“要塞曲毫”茶的研究

机制“要塞曲毫”具有茶索紧细卷曲、色泽绿润显毫、汤色绿亮、香高持久、滋味鲜醇等品质特征。机制该名优绿茶比手工制作工效提高６－８倍，成本节省３５％左右，经济和社会效益显著，文内具体介绍了机制“要曲毫”的充程及其制作技术。     

运用萎凋工艺改进银杏叶茶品质的研究

传统方法生产的银杏叶茶在香味上存在一种青腥气味 ,严重影响了这种保健茶消费市场的扩展。研究通过在杀青工序前增加萎凋工序 ,使叶子中的青腥气味随着萎凋时间和强度的增加而渐渐减轻 ,直至消失并出现花香。由于萎凋使叶内还原糖、游离氨基酸含量的增加 ,茶汤的滋味和香气有明显的改进。试验还表明 ,不同萎凋处理方式对银杏叶茶品质改进的效果不同 ,V3 处理的改进效果最好。对春嫩叶银杏叶茶品质改进的效果 ,明显地优于萎凋对秋成叶的品质改进效果。     

青心大冇品种加工东方美人茶工艺探究

指出了以青心大冇茶树品种加工东方美人茶工艺,以"偏重晒青,重做青,文焙火,二次烘焙"为宜。与黄旦、金牡丹制作的东方美人茶相比,感观审评结果为有白毫、显五色,花蜜香或花果香浓郁持久,汤色橙黄亮,滋味浓爽、花果香浓,叶底均匀,品质优异,适宜推广。     

Improving the antibacterial activity against Staphylococcus aureus of composite sheets containing wasted tea leaves by roasting

We used various kinds of wasted tea leaves to develop composite sheets with antibacterial properties. Antibacterial tests showed that the number of viable bacterial cells for the sheet containing wasted green tea leaves was around 10:⁶–10⁷ CFU/ml after 18 h culture compared to 108 CFU/ml for a tea-free sheet. This indicates that cell growth was signifi cantly inhibited. For sheets containing other types of tea leaves (oolong, black, hojicha, and pu-erh), living cells were not found, indicating that these sheets had superior antibacterial effects. Living cells were also not found in sheets containing wasted black tea leaves or roasted tea leaves at a concentration of 60% by weight after 6 h cultivation. Therefore, roasting treatment of wasted green tea leaves was examined to improve the antibacterial activity of the sheet. In particular, the focus was on structural conversion of catechins by heating.     

香椿茶叶不同制作工艺比较

以汤色、滋味、外型、香味及叶底为评判指标,比较香椿茶叶不同制作工艺。结果表明:处理方案A为最佳工艺,即材料选用嫩绿叶,采用微波杀青,造形为颗粒状,于90℃烘干3 h。处理方案B效果较好,其工艺为材料选用嫩绿叶,采取烫漂方式杀青,造形为颗粒状,于90℃烘干3 h。     

Synergetic deodorant effect and antibacterial activity of composite paper containing waste tea leaves

Composite paper containing waste tea leaves was prepared to investigate the effective utilization of waste tea leaves as deodorant material. Paper containing waste green tea leaves did not have increased deodorizing ability compared with controls either against acidic odors such as hydrogen sulfide and acetic acid gases or against neutral odors such as formaldehyde and acetaldehyde gases. In contrast, the paper had excellent deodorizing ability against basic odors such as ammonia and trimethylamine gases. It was observed during additional tests conducted on paper samples containing 60 wt% waste leaves of oolong tea, black tea, pu-erh tea, or hojicha, that all the samples reduced the ammonia concentration to below 1 ppm, which is the threshold concentration for olfactory recognition, within 30 min. Further, paper containing waste green tea leaves was found to decrease the odor residual rate to 5.1% in 30 min even for a waste tea leaf content of 10 wt%. The excellent deodorizing ability of the paper could be attributed to the chemical reactions between odorous substances and the catechins found in tea leaves. After the deodorization of ammonia, paper containing waste green tea leaves was found to have increased antibacterial activity against Staphylococcus aureus.     

Alpha-glucosidase inhibitory effect of mulberry (Morus alba) leaves on Caco-2

The effects of brewing time on dry weight content and alpha-glucosidase inhibitory active component released from mulberry (Morus alba) tea were studied. Different tea products showed significant differences in inhibitory activity against both sucrase and maltase. The most effective enzyme inhibition was observed when 3 to 5 min brewing time was applied in tea preparation. In a Caco-2 cell culture experiment the tea reduced the liberated glucose contents in both apical and basal sides of the cell monolayers. It can be concluded that hot water extract of mulberry leaves does have inhibitory effect against alpha-glucosidases, sucrase and maltase enzymes, and has a potential to be consumed as antidiabetic herb tea.     

采后处理方式对五倍子品质的影响

对比了蒸汽烫漂(SB)和沸水浸烫(BWB)2种预处理方式对新鲜五倍子的影响,以及经过预处理后分别采用烘箱干燥(OD)、流化床干燥(FBD)、自然干燥(ND)和紫外光辐照(UVI)4种干燥方式所得五倍子产品的品质。对干燥速率及产品指标的分析结果表明:预处理后五倍子含水率和单宁酸含量均有所降低,尤其是蒸汽烫漂后,含水率降为47.68%,与未处理五倍子含水率(55.77%)呈显著性差异;加热处理会使五倍子干燥产品中单宁酸的含量降低而没食子酸的含量增加,自然干燥的五倍子单宁酸质量分数在50.12%~56.84%之间,没食子酸质量分数在0.29%~0.46%之间,而烘箱干燥后五倍子中单宁酸质量分数仅为32.48%~42.43%,没食子酸质量分数高达2.97%~4.39%;不同采后处理方式对产品品质有不同的影响,沸水浸烫或蒸汽烫漂与紫外光辐照相结合可提高五倍子的干燥速率,且对产品单宁酸含量影响较小;烘箱和流化床干燥可将干燥时间降为5 h以内,但所得五倍子产品中单宁酸质量分数显著降低,均在32%~43%之间;沸水浸烫或蒸汽烫漂后自然干燥能保证单宁酸的结构最接近原始状态,但干燥时间高达200 h以上;所以可根据实际的操作条件和后续的应用选择五倍子的采后处理方式。工业化五倍子的采后处理因更注重干燥效率,以蒸汽烫漂预处理辅之以流化床干燥方式为佳。     

Preparation and properties of waste tea leaves particleboard

Urea-formaldehyde (UF) adhesive is the main source of formaldehyde emission from UF-bonded boards. The components in waste tea leaves can react with formaldehyde to serve as a raw material in the production of low formaldehyde emission boards. In our study, waste tea leaves and UF adhesive were employed in the preparation of waste tea leaves particleboard (WTLB). An orthogonal experimental method was applied to investigate the effects of process parameters on formaldehyde emission and mechanical properties of WTLB. The results indicated that: 1) waste tea leaves had the ability to abate formaldehyde emission from boards; and 2) density of the WTLB was a significant factor affecting its modulus of rupture (MOR), modulus of elasticity (MOE) and internal bonding (IB).     

锰对苦丁茶化学品质的影响

为探讨锰对苦丁茶化学品质的影响,采用国际通用的营养液配方对苦丁茶进行砂培盆栽试验。结果表明：MnCl2·4H2O对苦丁茶叶片中游离氨基酸、可溶性蛋白、维生素C等含量的提高非常有利。锰处理苦丁茶30 d后,上述各物质含量均随着锰质量浓度的增加呈先增加后降低的变化,而锰和皂苷则随着质量浓度的增加而增加。MnCl2·4H2O质量浓度为6.0 mg/L时,苦丁茶叶片中可溶性蛋白、维生素C、黄酮及茶多酚含量最高,此质量浓度对提高这几种化学物质含量较好;MnCl2·4H2O质量浓度为8.0 mg/L时,苦丁茶叶片中锰和皂苷含量最高,分别为0.555μg/g和0.828 mg/g。酚氨比随着锰质量浓度的增加先增加后降低。以MnCl2·4H2O质量浓度为6.0mg/L时茶多酚、黄酮、游离氨基酸和可溶性蛋白含量最高,品质良好,开发利用价值相对较好。     

湖南特种绿茶的主要化学成分

测定和分析了湖南省25只具代表性的特种绿茶的主要生化成分。结果表明：特种绿茶的全氮、游离氨基酸和咖啡碱的含量均高于普通绿茶，而可溶性糖和粗纤维的含量则低于普通绿茶；就品质成分来分析，产于山区的特种绿茶优于产于丘陵区的；茶树品种和原料嫩度均影响特种绿茶的主要生化成分含量。根据研究结果，作者提出了湖南名优茶在生产时间上限制在早春，在生产布局上应以山区为主，结合有特殊条件的其他地区来发展名优茶，在生产原料上，应以一芽一叶为主，适当考虑有特色的茶芽和一芽二叶初展的情况。     

浯峰贡茶的栽培管理与加工工艺

从茶园的精心培育与管理(包括种植密度、施肥种类及用量配比、修剪时间及方法、抚育管理等)和加工方法的改良(包括加工机械的选择与更新、鲜叶的采摘分级、鲜叶的摊放方法、炒茶工艺及其参数控制)等方面入手,采用对比分析的方法,探索出了浯峰贡茶的栽培管理措施与加工工艺;即采用矮化密植的栽植方式,早施、重施肥料且多施有机肥,提前修剪(改春剪为秋剪)和茶园铺草,能有效地增强茶树的抗旱抗寒能力,提高单位面积的产叶率和优质鲜叶的比例;并将传统的一锅到底的加工方法改变为青锅、摊凉和解锅等多程序炒茶工艺,采用这一技术,特别是在时间、温度、投叶量和含水率等参数上严格控制好,可使生产出来的茶叶成品色绿、形美、香郁、味甜．