临安市茶叶揉捻机发展史（二）

介绍了临安水力自动揉捻机及其用于控制揉捻程度的计数器的创制与应用。     

临安市茶叶揉捻机发展史（一）

介绍了临安市茶叶揉捻机的50年发展史。本篇介绍木质手推揉捻机的结构与特点。     

茶叶揉捻机的艺术造型设计

茶叶揉捻机的艺术造型设计杨松（湖北五峰茶叶机械厂邮编４４３４００）编者按茶叶揉捻机的艺术造型设计一文很有点新意，值得一谈。茶叶机械属于农业机械范畴，一向以经济、实用为设计的指导思想。这无疑是对的。但经济实用并不等于就是粗陋呆板。如果我们能在保持经济性...     

Antioxidant activities of crude tea polyphenols, polysaccharides and proteins of selenium-enriched tea and regular green tea

The crude tea polyphenols, polysaccharides and proteins of regular green tea and Se-enriched green tea were investigated in vitro for antioxidant activities by auto-oxidation test (AAPH) and α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging method. Results showed that crude tea polyphenols of Se-enriched green tea provided the highest antioxidant activity by DPPH assay and the antioxidant activity was decreased in the order: crude tea polyphenols > crude tea proteins > tea polysaccharides. The crude protein of Se-enriched green tea was found to exhibit the highest antioxidant activity by AAPH method and the antioxidant activity was decreased in the order: crude tea proteins > tea polyphenols > tea polysaccharides. Tea polyphenols and tea polysaccharides of Se-enriched green tea presented significantly higher antioxidant activities than that of regular green tea. No significant difference of antioxidant activities was found between crude tea proteins of Se-enriched green tea and regular green tea. The combinations of Se with tea polyphenols and tea polysaccharides were responsible for the higher antioxidant activities of Se-enriched green tea than regular green tea.     

Total content and speciation of aluminium in tea leaves and tea infusions

A total of 29 tea samples of different origin, 13 green tea samples, 13 black tea samples, two semi-fermented and one white tea, imported to the Czech Republic, were collected and analysed for total content of aluminium (Al) in tea leaves and tea infusions, as well as for Al compounds in these infusions. The total content of metals in tea leaves differs according to the type of tea (green or black) and is probably influenced by many factors, e.g., soil properties. The HPLC/IC speciation of Al in tea infusions was performed for all samples. The addition of Al³⁺ to the tea infusion proved that Al³⁺, Al(Y)²⁺ and Al(X)¹⁺ species can be determined in tea infusions. Increased extraction time did not show any affect on Al speciation, neither did the addition of sugar. After the addition of lemon juice, the speciation changed in one sample of black tea and five samples of green tea. These findings suggest that lemon juice as an additive can significantly influence Al speciation in tea infusions.     

Changes in content of organic acids and tea polyphenols during kombucha tea fermentation

Kombucha tea is a fermented tea beverage produced by fermenting sugared black tea with tea fungus (kombucha). Tea polyphenols which includes (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG) and theaflavin (TF) have been reported to possess various biological activities. The present study focused on changes in content of organic acid and tea polyphenols in kombucha tea prepared from green tea (GTK), black tea (BTK) and tea manufacture waste (TWK) during fermentation. Concentration of acetic acid has reached maximum up to 9.5 g/l in GTK on 15th day and glucuronic acid concentration was reached maximum upto 2.3 g/l in BTK on 12th day of fermentation. Very less concentration of lactic acid was observed during the fermentation period and citric acid was detected only on 3rd day of fermentation in GTK and BTK but not in TWK. When compared to BTK and TWK very less degradation of EGCG (18%) and ECG (23%) was observed in GTK. TF and thearubigen (TR) were relatively stable when compared to epicatechin isomers. The biodegradation of tea catechins, TF and TR during kombucha fermentation might be due to some unknown enzymes excreted by yeasts and bacteria in kombucha culture.     

Mechanisms of hypolipidemic and anti-obesity effects of tea and tea polyphenols

Among the health-promoting effects of tea and tea polyphenols, the cancer-chemopreventive effects in various animal model systems have been intensively investigated; meanwhile, the hypolipidemic and antiobesity effects in animals and humans have also become a hot issue for molecular nutrition and food research. It has been demonstrated that the body weights of rats and their plasma triglyceride, cholesterol, and LDL-cholesterol have been significantly reduced by feedings of oolong, black, pu-erh, and green tea leaves to the animals. It has been suggested that the inhibition of growth and suppression of lipogenesis in MCF-7 breast cancer cells may be through down-regulation of fatty acid synthase gene expression in the nucleus and stimulation of cell energy expenditure in the mitochondria. The experimental data indicated that the molecular mechanisms of fatty acid synthase gene suppression by tea polyphenols (EGCG, theaflavins) may invite down-regulation of EGFR/PI3K/Akt/Sp-1 signal transduction pathways.     

茶色素和茶多酚防癌作用的研究

为了解茶色素和茶多酚的防癌作用，用1组体外短期试验，检测茶多酚和茶色素在肿瘤的“启动”、“促癌”和“增殖”3个不同阶段的作用。结果表明茶多酚和茶色素对丝裂霉素(MMC)的致突变性及致微核形成均有明显的抑制作用；茶多酚和茶色素可明显阻断促癌物12-0-四葵酰基-佛波-13-乙酸酯(TPA)的促癌作用；明显抑制Hela细胞在软琼脂中形成集落的能力和降低Hela细胞的存活率；对荷瘤小鼠体内瘤体生长有一定的抑制作用。在本实验条件下茶多酚和茶色素对癌症形成3个阶段均有抑制作用。     

奶茶的研制

对奶茶的加工工艺进行研究，实验证明：添加β-CD和蜂蜜可以防止茶汤中“茶凝乳”的形成，当花生乳：牛乳：茶汤＝1：1：1时，奶茶成品的色，香，味均佳，使用蔗糖脂肪酸酯和单甘酯为乳化剂、海藻酸钠作为稳定剂，可以防止奶茶分层。     

中外茶艺术的历史展示及其多样风格

中国的茶艺术源远流长又形式多样，其中尤以绘画及装饰作品最为丰富。中国独特的茶画艺术构成了中国饮茶艺术品的主体形态，而世界各国的茶艺术品也都有其表达的独立方式：本文主要从艺术品实物的角度来展示历史上的中外茶艺术，并尽可能地阐发其特有的历史价值与艺术价值。     

The role of tea and tea flavonoids in cardiovascular health

Consumption of green or black tea has been inversely associated with the development and progression of cardiovascular diseases. In this review, the current knowledge about protective effects of tea and tea constituents, particularly flavonoids, on the cardiovascular system is summarized. Underlying mechanisms for the beneficial effects of tea include vasculoprotective, antioxidative, antithrombogenic, anti-inflammatory, and lipid-lowering properties of tea flavonoids. Although promising experimental data on beneficial effects of tea in various cardiovascular diseases are available, results of clinical studies in humans are not uniform. A number of factors are discussed which may contribute to inconsistent data in humans. Overall, tea represents a promising tool for the prevention and treatment of cardiovascular disorders.     

茶饮料无菌冷灌装工艺及设备

介绍了茶饮料无菌冷灌装生产工艺及设备。以此技术加工的产品能最大限度地保持茶饮料原有的营养成分和风味，而且极大地降低了生产成本，具有较好的经济效益和发展前景。     

茶叶保鲜技术及质变成因的比较研究

试验对炒青绿茶的贮藏保鲜技术进行了比较研究。结果表明，温度主要是通过减缓茶叶氨基酸的陈化速度而起保鲜作用的；保鲜剂对延缓茶多酚、氨基酸的陈化速度作用明显，并且还提出了当前市售保鲜剂的最佳保鲜期限为3个月，在使用保鲜剂进行茶叶贮藏过程中，应当明确了解保鲜剂的保鲜期限并运用合理的贮藏方法。光照、不同包装材料等因素在茶叶贮藏过程中对茶叶品质成分（茶多酚、氨基酸、咖啡碱）的变化影响均较大。