不同种类微生物对普洱茶发酵过程的影响

为阐明微生物在普洱茶发酵过程中作用机制,进行了普洱生茶单菌发酵实验,通过跟踪不同菌种对普洱茶发酵过程中感官品质和理化指标的影响,发现不同微生物对普洱茶发酵的作用,并对优势菌种进行混菌发酵实验,以期为工业化微生物发酵普洱茶提供理论和数据支持。结果表明,普洱茶发酵过程中,叶色由黄绿变为猪肝色,茶汤的苦涩感逐渐减弱,汤色红浓明亮,理化成分中茶多酚和水浸出物含量均减少,茶褐素和咖啡碱含量增加,且霉菌对这些成分的影响最大,酵母次之,细菌最小。混菌发酵茶样20d即具有普洱熟茶的品质。结果证明采用合理配比微生物发酵普洱茶可以缩短发酵时间,而且能更好地控制和规范普洱茶的发酵趋势和结果。     

普洱茶提取物对自发性高血压大鼠降压研究

采用自发高血压大鼠（SHR）进行普洱茶提取物降压功效的研究。给予普洱茶提取物0.25、0.5、1.0、2.0g/kg灌胃4周,观察动物的血压、心率、体重变化。结果显示,以普洱茶提取物1.0g/kg和2.0g/kg灌胃4周,对动物的平均动脉压、收缩压和舒张压均有降低作用,与模型组间存在显著差异（P<0.01）。普洱茶提取物0.25g/kg和0.5g/kg组动物血压较模型组没有显著性改变。普洱茶提取物2.0g/kg可提高动物的心率,有抑制其体重增长的趋势;其他剂量组动物的心率及体重增长均无显著变化。研究表明,普洱茶提取物对自发高血压大鼠具有降压作用,且具有剂量依赖性。     

遮荫对茶树新梢叶绿素及其生物合成前体的影响

研究了遮阳网遮荫处理对鸠坑、龙井43、水古新梢叶绿素生物合成前体物质和新梢叶绿素积累的影响。结果显示：遮荫降低光照强度,茶树新梢叶绿素含量显著增加;同时叶绿素生物合成的前体物质δ-氨基酮戊酸（aminolevulinic acid, ALA）、卟啉胆色素原（porphobilinogen, PBG）、尿卟啉原Ⅲ（Urogen Ⅲ）等含量降低,而原卟啉Ⅸ（protoporphyrin Ⅸ, ProtoⅨ）、镁原卟啉Ⅸ（magnesium protoporphyrin Ⅸ, Mg-ProtoⅨ）、原叶绿素酸酯（protochlorophyllide, Pchlide）含量升高。     

反复冷冻-解冻对鲢品质的影响

研究鲢(Hypophthalmichthys molitrix)在冷冻-解冻过程中的品质变化规律。鲢于–18℃条件下冻藏10 d,流水解冻后再贮藏于–18℃条件下,5 d后解冻,共反复冷冻-解冻5次。在解冻1、3、5次后随机取3条鲢测定其解冻损失、蒸煮损失、硬度、咀嚼性、恢复性、硫代巴比妥酸(TBA)值、L*值、b*值、盐溶性蛋白(SSP)含量、Ca2+-ATP酶活性、总巯基含量、表面疏水性和感官值等指标,评价反复冷冻-解冻对鲢品质的影响。结果表明,在第1次冷冻-解冻时,硬度、咀嚼性、恢复性、盐溶性蛋白(SSP)含量和Ca2+-ATP酶活性与鲢初始值相比显著降低(P<0.05),b*值和表面疏水性显著升高(P<0.05);解冻损失、L*值和TBA值在第3次冷冻-解冻时显著上升(P<0.05);总巯基含量在第5次冷冻-解冻时显著下降(P<0.05);而蒸煮损失在冷冻-解冻过程中没有显著变化(P>0.05);感官值在第5次冷冻-解冻时为47,感官品质已不可接受。各指标变化表明,鲢品质会随着反复冷冻-解冻次数增加而下降,在运输、贮藏和销售过程中要防止温度波动,避免反复冻融对鲢品质造成不利影响。     

Effects of Chemical Components on the Amount of Green Tea Cream

The relationship between the amount of tea cream and the chemical components contents in the original green tea infusion was investigated. The results showed that the amounts of tea cream in the green tea infusions obtained from different cultivars and different parts of new shoots were varied. There were many chemical components participating in the formation of green tea cream. However, there were only the contents of caffeine (Y=0.85, P＜0.01) and polyphenols (Y=0.65,P＜0.05) in the original green tea infusion highly correlated with the amount of green tea cream. Stepwise regression analysis of overall chemical components indicated that the contents of caffeine and gallated catechins in the original green tea infusion had a significant effect (P＜0.0 1) on green tea cream levels. Cream (g L-1)=-172.071+ 0.129×Ccaffeine+0.024×Ggallated catechins (R2=0.936). The amount of green tea cream can be predicted by the contents of gallated catechins and caffeine in the original tea infusion. Principal component analysis also indicated that catechins, minerals, and polysaccharides were the important chemical components in the formation of green tea cream.     

利用茶渣提取水不溶性膳食纤维

在分析茶渣主要成分含量基础上,研究以酸、碱处理和脱脂制备茶叶水不溶性膳食纤维.结果表明,酸的种类对水不溶性膳食纤维含量的影响不显著,pH的影响显著.在考察HC1溶液的pH、温度及时间对水不溶性膳食纤维含量的单因素影响规律基础上,采用L9(34)正交试验优化酸提取工艺,优化的结果为:pH为1、温度90℃、时间1.5 h,...     

绿茶生产质量信息管理系统设计与实现

为提高茶叶生产的质量安全监控信息化水平及茶叶生产企业管理的信息化水平,减少因茶园施肥、用药、加工等所造成的茶叶质量安全问题,将信息技术和茶叶生产质量管理关键控制点结合起来,采用计算机技术、网络数据库技术,设计并开发了绿茶生产质量信息管理系统,实现了绿茶产地环境、种植环节、加工过程及包装储运等质量关键控制点信息的网络化管理。     

2006-2009年宁德市茶叶5种农药残留检测分析

对福建省宁德市2006-2009年1738份茶叶样品,采用气相色谱仪检测三氯杀螨醇、氰戊菊酯、氯氰菊酯、甲氰菊酯、滴滴涕等农药残留含量,获取相应的检测数据,以国内制定的农药最大残留量为指标进行分析评估,结果表明,2006-2009年该市茶叶中农药残留检出超标率呈逐年下降的趋势,但是滴滴涕等农药仍有较高检出率,说明菊酯类...     

Establishment of core collection for Chinese tea germplasm based on cultivated region grouping and phenotypic data

Tea is an important economic crop in China. About 2665 accessions of tea germplasm (Camellia spp.) are conserved in the China National Germplasm Tea Repository. However, only a small fraction of the collections have been exhaustively used in tea plant improvement programs. The objective of the present study was to develop a core collection of tea plant to enhance the utilization of genetic resources in improvement programs and simplify their management. For this purpose, based on the cultivated region grouping and phenotypic trait data, a core collection of tea plant was established using logarithm proportion and Ward’s cluster method. Approximately 20% of the accessions were then randomly selected from these distinct groups to form a core collection of 532 accessions. Different statistical methods including comparison of mean using Newman-Keuls test, variance using Levene’s test, and frequency distribution using Chi-square test for the traits validated that the variation present in the initial collection was retained in the core collection. The Shannon-Weaver diversity index for different traits was also similar in the core and initial collection. The phenotypic correlations among different quantitative traits that may be under the control of coadapted gene complexes were also preserved in the core collection. This core collection will play an important role in the utilization of tea germplasms.     

明清以来闽台茶产业发展史研究进展

福建历来为产茶大省,明清以来其茶产业发展对台湾有重要影响。闽台茶产业的互动模式和发展路径,在世界茶产业界举足轻重,对其学术价值则尚待挖掘。明清以来闽台茶业演进过程中,产生了一批著名茶商,其经营思想和业绩,对当前我国茶业发展仍具借鉴意义。该文对台湾和大陆关于明清以来闽台茶业发展史的文献进行了较系统和全面的梳理和综述,以此为基础,从以茶为缘、以商为本、以技为重、以史为鉴四个方面,提出进一步深化和拓展该领域研究的建议。