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1.
红茶色素及其分光光度法   总被引:7,自引:0,他引:7  
红茶色素是从红茶茶汤中萃取分离的一类色素物质,是多酚类及其衍生物氧化聚合缩合产物,主要在发酵过程中形成的,是影响红茶品质最为重要的因素。Roberts E.A.H.等(1957)将红茶茶汤中溶于乙酸乙酯呈橙黄色的物质称为茶黄素,不溶于乙酸乙酯呈褐红色的物质称茶红素。随着生化技术的进步与应用,红茶色素化学有重大进展,尤其是茶黄素化学研究的成就使茶黄素的提取、分离、纯化和在制茶中的形成机制及其与红茶品质的关系等均已明晰。茶黄素是一类苯并(?)酚酮的衍生物,主要组分有茶黄素、茶黄素单没食子酸酯和茶黄素双没食子酸酯。茶红素化  相似文献   

2.
红茶色素的系统分析法   总被引:2,自引:1,他引:1  
红茶色素是指茶多酚在红茶制造过程中所形成的有色氧化产物,这些氧化产物归纳起来可分为三大类:茶黄素类、茶红素类、茶褐素类。茶黄素是一类呈橙黄色的物质,它是构成茶汤明亮度和滋味鲜爽度的主要组成成分;茶红素呈红色,是红茶汤色的主体物质;茶褐素是一类呈棕褐色的物质,是形成暗汤的基本因素。优良品质的红茶含有较多的茶黄素和茶红  相似文献   

3.
红茶品质影响因素的研究进展   总被引:1,自引:0,他引:1  
正红茶属于全发酵茶,在加工中利用酶促氧化作用,使茶叶中的多酚类物质等内含物氧化、聚合、缩合生成茶黄素、茶红素等有色物质,形成红茶"红汤红叶"、香气甜香、滋味甜醇的品质特征。近年国内红茶发展迅速,关于红茶品质的研究引起关注。本文就产地环境、茶树的品种、加工工艺和外源酶等对红茶品质的影响等方面的研究进行综述,以期探讨红  相似文献   

4.
冷冻萎凋对工夫红茶品质的影响   总被引:6,自引:0,他引:6  
工夫红茶多年来一直沿用重萎凋、重发酵的传统工艺,因而其色素的种类和数量均大大低于CTC红茶,滋味不够浓强.有研究表明,采用冷冻萎凋能缩短萎凋和发酵时间,有利于改善红茶品质;但也有研究显示,冷冻萎凋过程中酶活性较低,限制了必要的物质转化,因而可能对红茶品质有负面影响.本项研究就冷冻萎凋对工夫红茶生化成分变化及品质的影响作了较为全面的研究,旨在探明利用冷冻萎凋改善红茶品质的可行性.  相似文献   

5.
萎凋技术对工夫红茶品质影响研究进展   总被引:1,自引:0,他引:1  
工夫红茶的加工工艺中,萎凋是第一道丁序,是形成红茶品质的基础工序。茶鲜叶经过萎凋,既有物理方面的失水,也有化学方面的物质转化。影响萎凋品质的因素主要有萎凋方式、萎凋时间、萎凋温度及萎凋程度等,萎凋效果对红茶最后品质的形成影响较大。因此,本文通过综述萎凋方式、萎凋时间、萎凋温度及萎凋程度对工夫红茶品质的影响,并提出建议,以期生产企业能在实际生产中对萎凋工序及萎凋各因子对红茶品质的影响有足够的认识,为生产优质红茶和新工艺产品开发提供一些帮助。  相似文献   

6.
红茶加工工艺是使鲜叶中的多酚类在多酚酶氧化作用转化为二聚或多聚色素(茶黄素、茶红素)的过程。关于茶叶化学成分与红茶品质的关系,目前已有过许多研究。这些研究发现红茶品质决定于鲜叶化学成分和  相似文献   

7.
萎凋是红茶加工的关键工序之一,萎凋环境对红茶品质的形成有重要影响。张雁飞等比较了传统萎凋、鲜叶冷冻以及冷冻萎凋工艺对祁门红茶品质的影响,发现冷冻萎凋工艺制得的红茶除可溶性糖略低外,其余成分含量均高于传统萎凋方式,但香气组分萜烯类物质、香叶醇、苯乙醇等祁红特征物质含量低于传统萎凋。黄建琴也发现冷冻萎凋能明显缩短工夫红茶的萎凋和发酵时间,增加红茶的茶黄素和茶红素含量,提高滋味和汤色品质,但冷冻萎凋降低了葡萄糖酶活性,对红茶香气的形成有一定影响。  相似文献   

8.
发酵程度对红茶品质的影响   总被引:1,自引:0,他引:1  
汪开华  陈贞纯  屠幼英 《茶叶》2012,(3):168-171
随着越来越多的消费者对红茶健康功能的认识,近五年国内红茶生产和销售增加非常迅速。红茶的发酵程度极大地影响红茶的品质,发酵是形成红茶品质特征的主要工序。本文从红茶发酵程度的把控和界定为切入点,详细探讨了原料、发酵温度、发酵湿度、发酵时间、发酵通氧量、发酵叶堆积厚度等因素对红茶品质的影响,以及应如何控制这些因素以生产品质优越的红茶。旨在为红茶生产企业以及科研人员提供实际指导意见。  相似文献   

9.
工夫红茶是我们日常饮用中最常接触的红茶种类,也是我国独特的传统红茶产品。我国工夫红茶产地众多,所产红茶多以产茶地命名,独特的品种、生态等条件,造就了其品质间的差别。虽然品质之间存在区别,但鉴别工夫红茶的大体方向是确定的,本期茗茶尚品讲主要介绍工夫红茶审评时的要点。  相似文献   

10.
郑火娇 《福建茶叶》2011,33(4):29-32
中国是红茶的创始国,红茶在世界上拥有广泛的爱好者。随着红茶受到越来越多茶叶爱好者的喜爱,如何进一步提升红茶品质,生产出满足市场消费需求的红茶也日益成为人们普遍关注的问题。本文拟从红茶品质的形成机理为切入点,探讨影响红茶品质的因素,并以此探讨改进与提升红茶品质的相关措施,旨在为茶叶生产技术人员以及科研人员提供一些参考。  相似文献   

11.
随着早熟晚粳、中熟晚粳广泛种植,水稻轻型省力栽培方式旱直播的推广,病虫也发生了变化,成熟期显著推迟,下茬无法在适宜播期种植,影响粮食丰产稳产。提出筛选早熟当家品种、大力推广机插秧、加大粮食烘干设备的投入、合理施肥、精准植保等对策。  相似文献   

12.
Sorghum is a good source of phenolic compounds with a variety of genetically dependent types and levels including phenolic acids, flavonoids, and condensed tannins. Most sorghums do not contain condensed tannins, but all contain phenolic acids. Pigmented sorghums contain unique anthocyanins that could be potential food colorants. Some sorghums have a prominent pigmented testa that contains condensed tannins composed of flavan-3-ols with variable length. Flavan-3-ols of up to 8–10 units have been separated and quantitatively analyzed. These tannin sorghums are excellent antioxidants, which slow hydrolysis in foods, produce naturally dark-colored products and increase the dietary fiber levels of food products. Sorghums have high concentration of 3-deoxyanthocyanins (i.e. luteolinidin and apigenidin) that give stable pigments at high pH. Pigmented and tannin sorghum varieties have high antioxidant levels that are comparable to fruits and vegetables. Finger millet has tannins in some varieties that contain a red testa. There are limited data on the phenolic compounds in millets; only phenolic acids and flavones have been identified.  相似文献   

13.
Sorghum and millet phenols and antioxidants   总被引:5,自引:2,他引:5  
Sorghum is a good source of phenolic compounds with a variety of genetically dependent types and levels including phenolic acids, flavonoids, and condensed tannins. Most sorghums do not contain condensed tannins, but all contain phenolic acids. Pigmented sorghums contain unique anthocyanins that could be potential food colorants. Some sorghums have a prominent pigmented testa that contains condensed tannins composed of flavan-3-ols with variable length. Flavan-3-ols of up to 8–10 units have been separated and quantitatively analyzed. These tannin sorghums are excellent antioxidants, which slow hydrolysis in foods, produce naturally dark-colored products and increase the dietary fiber levels of food products. Sorghums have high concentration of 3-deoxyanthocyanins (i.e. luteolinidin and apigenidin) that give stable pigments at high pH. Pigmented and tannin sorghum varieties have high antioxidant levels that are comparable to fruits and vegetables. Finger millet has tannins in some varieties that contain a red testa. There are limited data on the phenolic compounds in millets; only phenolic acids and flavones have been identified.  相似文献   

14.
概述了海峡两岸农业交流与合作的现状,提出了应该共同呼吁尽快实现两岸“三通”,开放农业生物技术图书期刊资料交流以及开放生物学科方面网络的思路,以便为农业交流与合作的顺畅开展打好基础,并寄希望能够就糖蔗、果蔗以及甘蔗笋等方面的研究与开发到台湾学习取经,开展学术交流或与台湾同行共同开展研究,为我省甘蔗业的发展作出贡献。  相似文献   

15.
种子加工、检验理论与技术现状及思考   总被引:3,自引:0,他引:3  
种子加工及检验是种子向市场流通的关键,是商业化育种中赋予种子商品属性不可或缺的环节。种子加工、检验理论与技术的研究是完善种业产业链、实现规模化商业育种、夯实“育繁推一体化”种业科学的重要一环。中国的种业科学技术体系正在形成与完善之中,受制于行业发展水平,种子加工及检验理论与技术相对薄弱。本文回顾了种子加工及检验理论与技术研究发展历程,提出了完善中国种业科学发展的策略与建议。围绕种业发展的需要,在做好品种优质化繁育的基础上,分析种子加工及检验理论与技术的新方向和新需求,加强种业应用性研究,建立先进的种子质量检验体系,研制适合现代种业发展需求的种子加工设备,打造种子加工产业标准化生产体系,完善种业科学技术学科建设,促进种业产业持续健康发展。  相似文献   

16.
Summary Between 1993 and 1998 205 different potato cultivars and 1220 accessions/genotypes of wild and cultivated potato species from the IPK Genebank Gatersleben were evaluated. Parameters interesting for starch isolation and especially for the use of starch were determined. Altogether, there was a higher variability in wild potato species than in cultivated potatoes for all characteristics investigated: dry matter content, starch content, protein content, amylose content and mean particle diameter of starch granules.  相似文献   

17.
Yield and quality of winter and spring triticales for forage and grain   总被引:2,自引:0,他引:2  
In field experiments conducted over 2 years in Mediterranean conditions, five winter and five spring triticales were evaluated for forage and grain production in the same cropping season. The experiments had two treatments, namely harvesting for grain only, and dual-purpose forage and grain production. In the latter treatment, forage was cut when the first node was detectable (Zadoks' stage 31), without removing the apical meristems. Grain was harvested when ripe (Zadoks' stage 92) in both cut and uncut plots.
Environmental conditions affected grain production and protein content more than forage yield and quality. Winter triticales yielded about 43% more forage than spring types, but after forage removal the spring types yielded about 36% more grain than winter triticales.
Reductions in grain yield after clipping were more pronounced in winter (32%) than in spring (19%) types. Forage crude protein content was significantly higher in the spring types studied (24.6%) than in the winter types (23.5%), the opposite being true for fibre content (20.7 and 21.6% respectively). Grain crude protein content did not differ between grain and dual-purpose treatments, but was higher in the spring triticales (12.8%) than in the winter types (11.9%). There was more variability for the measured traits within the winter triticales studied than within the spring types.  相似文献   

18.
种子加工及检验是种子向市场流通的关键,是商业化育种中赋予种子商品属性不可或缺的环节。种子加工、检验理论与技术的研究是完善种业产业链、实现规模化商业育种、夯实"育繁推一体化"种业科学的重要一环。中国的种业科学技术体系正在形成与完善之中,受制于行业发展水平,种子加工及检验理论与技术相对薄弱。本文回顾了种子加工及检验理论与技术研究发展历程,提出了完善中国种业科学发展的策略与建议。围绕种业发展的需要,在做好品种优质化繁育的基础上,分析种子加工及检验理论与技术的新方向和新需求,加强种业应用性研究,建立先进的种子质量检验体系,研制适合现代种业发展需求的种子加工设备,打造种子加工产业标准化生产体系,完善种业科学技术学科建设,促进种业产业持续健康发展。  相似文献   

19.
Seed processing and testing hold the key to the market circulation of seeds, and are an indispensable link in commercial breeding to endow seeds with commodity attributes. The research of seed processing and testing theory and technology is an important link in improving the seed industry chain, realizing large-scale commercial breeding and consolidating the seed industry science of ‘integration of breeding, propagation and promotion’. The scientific and technological system of seed industry in China is being formed and perfected, which is subject to the development level of the industry. The theory and technology of seed processing and testing are relatively weak. We reviewed the development of seed processing and testing theory and technology, and put forward strategies and suggestions to improve the sound development of China’s seed industry. In order to meet the needs of seed industry development and on the basis of high quality breeding of varieties, the new directions and demands of seed processing and testing theory and technology were analyzed. We will work to strengthen the applied research of seed industry, establish advanced seed quality inspection system, improve seed processing equipment suitable for the development needs of modern seed industry, establish standardized production system of seed processing industry, develop the scientific and technological disciplines of seed industry, and promote the sustainable and healthy development of seed industry.  相似文献   

20.
1大豆花叶病毒病 大豆病毒病(Soybean Mosaic Virus,SMV)是世界性病害之一。我国东北地区已鉴定的有5种,即大豆花叶病、顶枯病、蚕豆萎蔫病、南方菜豆花叶病、花生条纹病毒。其中大豆花叶病在全国大豆主要产区都有发生,十分常见。  相似文献   

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