Types Of Tea Research Articles

三峡库区典型茶园土壤水分对不同降雨模式的响应

PDF HTML阅读 XML下载 导出引用 引用提醒 三峡库区典型茶园土壤水分对不同降雨模式的响应 DOI: 10.5846/stxb202201240232 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（42077065）；国家自然科学基金项目（U224022） Response of soil moisture in typical tea gardens to different rainfall regimes in the Three Gorges Reservoir Area Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:土壤水分是坡面产流和生物地球化学过程的关键控制因素。降水事件可以通过引起土壤剖面不同深度的土壤水分响应，从而影响流域中的径流路径、产流机制和土壤侵蚀过程等。基于三峡库区典型分布的茶园为对象，通过长期定点、高频的气象和水分数据观测，研究不同降雨模式下茶园不同土层深度（0-10、10-20、20-30、30-40cm）土壤水分的时空变化特征，分析茶园不同深度土壤在雨季的水分动态变化规律和对不同降雨模式的响应特征。结果表明：（1）研究区内的降雨和土壤水分含量均表现出明显的季节性特征。降雨在7月达到最大值，土壤水分含量则在8月达到峰值。表明降雨是影响土壤水分含量变化的重要因子，土壤水分对降雨有着明显的响应过程。（2）在相同降雨条件下，土壤含水量具有明显的垂直梯度变化。随着土层深度的增加，土壤水分对降雨的响应逐渐呈现出滞后现象。表层土壤（0-20cm）对降雨的响应较为迅速且幅度更加明显，深层土壤（30-40cm）水分含量变化相对稳定，并且对降雨的响应时间更加滞缓。随着土层深度的增加，土壤水分含量的变化幅度逐渐趋于平稳。（3）土壤水分含量对不同的降雨模式表现出显著差异。在较大雨强条件下，土壤水分变化出现了上升期、平台期及退水期。在小雨强短历时的降雨中，降雨对土壤水分的影响主要表现在土壤表层（0-10cm）。在降雨初期，降雨强度越大，土壤水分入渗越快，土壤的响应深度越深。研究三峡库区典型分布的茶园在不同降雨模式下的土壤水分变化特征，为三峡库区坡地的降水资源优化配置和园地面源污染防控提供理论依据，对区域水土流失治理以及面源污染物防控具有重要意义。 Abstract:Soil moisture is a key control factor for slope runoff generation and biogeochemical processes. Rainfall events can affect runoff paths, runoff mechanisms, and soil erosion processes in watersheds by causing soil moisture responses at different depths in the soil profile. Based on the typical tea gardens in the Three Gorges Reservoir Area, through long-term, fixed-point and high-frequency meteorological and moisture data observations, the temporal and spatial variation characteristics of soil moisture in different soil depths (0-10, 10-20, 20-30 and 30-40cm) of tea gardens under different rainfall regimes was studied, and the dynamic variation of soil moisture in the rainy season at different depths of tea gardens and the response characteristics to different rainfall regimes were analyzed. The results showed that:(1) The rainfall and soil moisture content in the study area showed obvious seasonal characteristics. Rainfall peaked in July and soil moisture levels peaked in August. It showed that rainfall was an important factor affecting the change of soil moisture content, and soil moisture had an obvious response process to rainfall. (2) Under the same rainfall conditions, soil water content had obvious vertical gradient changes. With the increase of soil depth, the response of soil moisture to rainfall gradually showed a hysteresis phenomenon. The topsoil (0-20cm) responds to rainfall more rapidly and the amplitude was more obvious, the change of water content in the deep soil (30-40cm) was relatively stable, and the response time to rainfall was more sluggish. With the increase of soil depth, the variation range of soil moisture content gradually became stable. (3) The soil moisture content showed significant differences with different rainfall regimes. Under the condition of high rainfall intensity, soil moisture changes appeared in the rising period, the plateau period and the retreating period. In the rainfall with small rainfall intensity and short duration, the effect of rainfall on soil moisture was mainly manifested in the soil surface layer (0-10cm). The greater the rainfall intensity, the faster the soil moisture infiltration, and the deeper the soil response depth were exhibited in the early stage of rainfall. Studying the characteristics of soil moisture variation characteristics in typical tea gardens in the Three Gorges Reservoir area under different rainfall patterns will provide a theoretical basis for the optimal allocation of precipitation resources and the prevention and controlling of ground source pollution in the gardens, which is of great significance to regional soil erosion control and the prevention and control of non-point source pollution. 参考文献 相似文献 引证文献

대차(大茶)·뇌원차(腦原茶)에 관한 연구

This study compared and analyzed the records of Dae Cha and Noewon Cha in Korean and Chinese historical records. This analysis showed that these two types of tea should be approached from an East Asian perspective, breaking the notion that had been recognized as unique domestic teas of Goryeo. In addition, Dae Cha and Noewon Cha are good research topics for understanding the negotiations of East Asian tea culture in the 10th century. An analysis of the records of the two countries suggested that Dae Cha was produced and used for 139 years from 909 to 1047 in the Wuyue, Min, and Goryeo dynasties. Noewon Cha may have existed throughout the Silla, Wuyue, and Goryeo Dynasties for 132 years, from 916 to 1047. Through this study, Dae Cha was produced in Muzhou, Zhejiang Province. Hence, the possibility that Noewon Cha could be Shilla's tea could be explored. In this paper, the Shilla theory, the Wuyue theory, and the Goryeo theory were raised in relation to the origin of Noewon Cha. In this study, some issues that need to be identified through future research have emerged. These include the problem with the name of Noewon Cha, which is marked differently in the records of the two countries, the problem of the production area of Noewon Cha, and the tea culture negotiation relationship between the countries that existed in the Korean Peninsula and the Chinese mainland in the 10th century. This study is expected to enrich the discourse of Dae Cha and Noewon Cha and give new vitality to research in this field.

대전 지역 중년 여성의 맥문동차에 대한 인지도와 기호도

The study investigated recognition and consumption of tea and preference for Liriope platyphylla tea and blended tea to provide basic data for developing Liriope platyphylla tea and foods. Subjects were middle-aged women and mostly housewives. Of these subjects, 61.1% liked tea. The main reason for liking tea was ‘health functionalities’. The majority of these subjects had made tea purchases. All factors showed above average importance when purchasing tea. Especially, ‘safety’ and ‘taste’ were considered the most important. More than half of these subjects did not have purchase experience of blended tea. Many of them explained that they did not have much information about blended tea. Also, a large proportion of subjects did not know blended tea very well. Awareness of Liriope platyphylla scored 2.61 of 5 on average. It was found that 76.4% of subjects did not have experience with food using Liriope platyphylla, indicating that awareness of Liriope platyphylla was low. Few subjects had experience with foods using Liriope platyphylla. Next, Liriope platyphylla tea and two types of blended tea showed an above average preference. Especially, subjects preferred blended tea consisting of Liriope platyphylla, brown rice, and Platycodon grandiflorus or consisting of Lycii fructus, Liriope platyphylla, and brown rice. Based on these results, the way to complement Liriope platyphylla with supplementary ingredients could be better than using only Liriope platyphylla when developing a beverage with Liriope platyphylla.

Implementasi Jaringan Syaraf Tiruan Backpropagation Pada Klasifikasi Grade Teh Hitam

Black tea is the most widely produced type of tea in Indonesia, where Indonesia itself is the 5th largest black tea exporter in the world. According to the provisions of SNI-1902-2016, the quality requirements of black tea through appearance include the shape, size and weight (density), and the color of the black tea particles themselves. This study aims to determine the workings of the backpropagation method and the implementation of python on black tea grade classification, and to determine the level MSE of accuracy in the results of black tea grade classification using backpropagation. The model used in this study uses 4 input layers, 5 hidden layers, and 3 output layers. In the input layer, 4 input variables are used, namely shape, size, density, and color. The results of the classification using backpropagation with a number of iterations of 1000 iterations on the training data obtained an error of 0.096.

Quality Characteristics and Antioxidant Activities of Commercial Leaf Tea Extract

Purpose: In this study, the physicochemical properties and antioxidant activities of 23 types of tea were analyzed. Through this study, we tried to provide the basic data for tea research.Methods: Leaf tea extracts were prepared using hot water at 70℃, and their physicochemical properties, such as color intensity and pH, were analyzed. The total flavonoid content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability, and α-glucosidase inhibitory activity were measured as antioxidant activity.Results: The color of most leaf tea extracts was brown, with black tea having the deepest color. Black tea had the highest total flavonoid content at 593 mg QE/g. Eoseongcho tea had the highest DPPH scavenging ability at 97.56%. The α-glucosidase inhibitory activities of black tea and Chinese bush-clover tea were strong, while those of mistletoe, plantain, and rosemary leaf teas were exceptionally low.Conclusion: Black tea which has excellent total flavonoid content, DPPH scavenging ability, and α-glucosidase inhibitory activity, is expected to be most effective functional tea when consumed after meals among the multi consumption commercial leaf teas market.

Characterization of Hypolipidemic Phenol Analogues from Fermented Tea by Eurotium cristatum

Fuzhuan brick tea (FBT), a type of black tea, is a traditional beverage in China, especially popular among frontier ethnic groups. FBT is well-known for its health benefits, such as hypoglycemic, anti-hypertensive, anti-inflammatory, diuretic, and detoxification effects. Nevertheless, the underlying mechanisms on the molecular level are still elusive and the key compounds responsible for the health benefits are unidentified. Previous studies have mainly focused on functional studies of the water extract. However, FBT is typically cooked with butter or milk. Therefore, we hypothesized that some lipophilic components in FBT, which can be absorbed through the co-consumption of butter or milk, may play an important role in the health benefits. The present study aimed to investigate whether the liposoluble extract of FBT alleviates symptoms related to metabolic diseases and to identify the active compounds involved. By comparing the high-performance liquid chromatography (HPLC) profiles of water, milk and hexane extract, some low polarity peaks were observed in the milk and hexane extracts. Furthermore, the hexane extract treatment alleviated body weight gain, serum total cholesterol and triglyceride levels, and inhibited the accumulation of hepatic fat granules in a high-fat diet (HFD)-induced C57BL/6N mouse model. In order to identify the key functional lipophilic compounds in FBT, the hexane extract of FBT was subjected to chemical characterization. Four phenol analogs were characterized, namely, isodihydroauroglaucin (1), dihydroauroglaucin (2), tetrahydroauroglaucin (3), and flavoglaucin (4). Compounds 1 and 4 reduced the levels of total cholesterol and triglyceride in vivo. Both compounds also inhibited the high-fat diet-induced body weight gain and accumulation of fat granules in the liver of C57BL/6N mice. Isodihydroauroglaucin and flavoglaucin have therefore been identified as bioactive ingredients that contribute to the health benefits of FBT.

Characterization of the Key Aroma Compounds in Different Aroma Types of Chinese Yellow Tea

Yellow tea is one of the six major tea categories in China. The floral fragrance type, high-fired fragrance type, fresh fragrance type, and corn-like fragrance type were the main aroma types of yellow tea screened by QDA. A total of 103 volatiles were identified in yellow teas by HS-SPME/GC-MS analysis. Using multivariate analysis and OAVs, forty-seven aroma compounds were identified as key aroma compounds for the formation of different aroma types of yellow teas. Among them, 8, 14, 7, and 18 key aroma compounds played an important role in the formation of aroma characteristics of floral fragrance, high-fired fragrance, fresh fragrance, and corn-like fragrance types of yellow teas, respectively. Furthermore, PLS analysis revealed that 12 aroma compounds were the key contributors to the 'floral and fruity' and 'sweet' attributes, five aroma compounds contributed to the 'roasted' attribute, and four aroma compounds related to the 'fresh' and 'grassy' attributes. This study provides new insights into the aroma characteristics formation of different aroma types of yellow teas and will provide a valuable theoretical basis for improving the flavor quality of yellow tea during the manufacturing process.

Applying Variable Selection Methods and Preprocessing Techniques to Hyperspectral Reflectance Data to Estimate Tea Cultivar Chlorophyll Content

Tea is second only to water as the world’s most popular drink and it is consumed in various forms, such as black and green teas. A range of cultivars has therefore been developed in response to customer preferences. In Japan, farmers may grow several cultivars to produce different types of tea. Leaf chlorophyll content is affected by disease, nutrition, and environmental factors. It also affects the color of the dried tea leaves: a higher chlorophyll content improves their appearance. The ability to quantify chlorophyll content would therefore facilitate improved tea tree management. Here, we measured the hyperspectral reflectance of 38 cultivars using a compact spectrometer. We also compared various combinations of preprocessing techniques and 14 variable selection methods. According to the ratio of performance to deviation (RPD), detrending was effective at reducing the influence of additive interference of scattered light from particles and then regression coefficients was the best variable selection method for estimating the chlorophyll content of tea leaves, achieving an RPD of 2.60 and a root mean square error of 3.21 μg cm−2.

Tea and Tea Product Diversification: A Review

Tea is the most consumed drink after water as well as is one of the prevalent and the cheapest beverage which consumed globally. Tea is considered a healthy beverage due to the presence of several antioxidants and minerals such as potassium, magnesium, calcium & manganese. Different kinds of teas are manufactured in different countries based on taste, habit and culture of the people. Normally, tea can be categorized into three groups: green tea (unfermented), Oolong tea (partially fermented) and black tea (fully fermented) based on tea processing. Tea is a rich source of polyphenols and now-a-days interest in the possible health benefits of polyphenols, particularly flavonoids, has increased owing to their antioxidant and free-radical scavenging abilities. The rising demand of tea is considered one of the significant components for the worldwide beverage market growth. Tea industry makes a vital contribution to the economy of the respective tea producing countries like China, Japan, India, Sri Lanka, Bangladesh, Kenya etc. At the present time with the rising demand of tea it is needed to emphasize for exploring alternative means of increasing profits from tea cultivation. The tea market price is low in Different countries like Srilanka, India, Bangladesh, Kenya etc. comprises with high cost of production. For this reason, there is no alternatives rather than product diversification of tea through value addition which can be an important approach to mitigate the impacts of low market price and high production costs. This review broadly focuses on the issues leading to the development of wide range of tea and tea product diversification. This paper is also associated health benefits with different types of tea, nutraceutical beverage, confectionary items, toiletries and cosmeceuticals which being commercialized in different parts of the world which are gaining consumer acceptance and also face the challenges of global marketing by tea industries that’s are described in this paper.

Does the Type Matter? Verification of Different Tea Types' Potential in the Synthesis of SeNPs.

Selenium nanoparticles (SeNPs) are gaining popularity due to their potential biomedical applications. This work describes their green synthesis using various types of tea. Black, green, red and white tea infusions were tested for the content of polyphenolic compounds and antioxidant properties and then used in the synthesis of SeNPs. In each of the syntheses, nanoparticles with dimensions ranging from 3.9 to 12.5 nm, differing in shape and properties, were obtained. All of them were characterized by a very high ability to neutralize hydroxyl radicals, which was about three-times higher than for the tea infusions from which they were obtained. The main inconvenience in obtaining SeNPs was the difficulties with their purification, which should be a further stage in the described research.

COMPARATIVE QUANTITATIVE ANALYSIS OF SOME CLASSES OF BIOACTIVE COMPOUNDS IN SOME TEA SORTIMENTS AND TEALIKE INFUSIONS AVAILABLE ON THE ROMANIAN MARKET

Two white tea types, Pai Mu Tan and Fujian blend and three popular non-tea infusions, yerba mate, rooibos and hibiscus tea were studied for determining the concentrations of chlorophyll, carotenoid, total phenolic and polyphenolic compounds and essential oil contents in raw plant material and pH of the resulting infusions.White teas had the highest average amount of chlorophylls (746 mg/kg Fujian, 1,164 mg/kg Pai Mu Tan), the same being valid for carotenoids (218-226 mg/kg). Among non-tea beverages, rooibos had the highest amounts of both chlorophylls and carotenoids.Total phenolic compounds also had the highest concentrations in white teas (43,617 mg/kg Pai Mu Tan, 47,522 mg/kg Fujian) followed by yerba mate (29,146 mg/kg). Total essential oils were much more variable, even among white teas (1,200-10,800 mg/kg), with high amounts in yerba mate and hibiscus tea.pH values were similar, mildly acidic, except for the highly acidic (1.31) hibiscus tea.

Effect of Using Different Preparation Methods on the Properties of CdS Nanoparticles

This study aims to prepare cadmium sulfide nanoparticles in two methods, which are the chemical method and the biological method using two types of extracts, green tea, and starch. The prepared nanoparticles were characterized by various techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), and Energy Dispersive X-ray Spectroscopy (EDX). The synthesis of crystalline CdS nanoparticles was confirmed by various analytical techniques such as X-ray diffraction (XRD) and the pattern reveals cubic and hexagonal structures. The average crystal size for the methods respectively is 11.5, 15.9, and 5.67 nm, which have a spherical shape for nanoparticles CdS by scanning electron microscopy (SEM). The peaks of cadmium and sulfur emerged in the assay (EDX). The energy gap of the CdS has increased than the energy gap of the bulk CdS, the results were 2.63, 2.88, and 3.06 eV, respectively. This is an evidence of obtaining a nano-material for CDS by these two methods.

Differential characterization of volatile components and aroma sensory properties of different types of Hehong tea (Congou black tea)

AbstractTo explore the flavour characteristics and their different molecular mechanisms of different types of Hehong tea (Gongya, GY; Congou, CG and Laocong, LC) from the perspective of dry tea, we investigated their volatile compounds and sensory aroma sub‐attribute characteristics by headspace–solid phase microextraction–gas chromatography–mass spectrometry (HS‐SPME‐GC–MS), quantitative description analysis (QDA), and chemometrics. A total of 42 volatile compounds were identified in Hehong tea, of which alcohol content was the highest, the number of esters was the largest and pyrrole showed the largest differences. The volatile components of GY and LC differed, whereas those of CG and LC were more similar. There were 34 volatile components with a significant difference in the three types of Hehong tea. We established the aroma quantitative system of Hehong tea by using QDA. We found that sweety was probably the symbolic aroma sub‐attribute of Hehong tea, and woody was the characteristic sub‐attribute of LC, and there was a certain correlation among the aroma sub‐attributes. A total of 21 volatile components importantly contributed to the aroma sub‐attributes of Hehong tea. Furthermore, we screened out 18 marker volatile compounds that may be used as important indicators for distinguishing the three types of Hehong tea. Our findings add to our understanding of the flavour characteristics and aromas of the three types of Hehong tea and provide new strategies and thoughts for the evaluation of tea flavour using dry tea.

Multiple response optimizations on the leached-spray-dried bancha green tea towards healthy ageing

Bancha is a popular type of green tea in Japan, rich in tea polyphenols (TPs) and has a more astringent aroma with a less aromatic and strong character that complements functional foods. The blanching process is used to extract TPs and remove unwanted microorganisms, as well as inhibit phenolic oxidation. This study proposed a green tea blanching process followed by spray drying the extracts with maltodextrin. Furthermore, it is focused on maximizing the major chemical components of green tea (i.e., catechins, caffeine, and phenolic contents) based on powder particle size obtained through Multiple Response Surface Methodology optimizations. The results show that the proposed model accurately predicts leached-spray dried green tea's total catechin and caffeine content, with a coefficient of 0.9475 and 0.8692, respectively. This process yielded composite desirability of 0.9751, while individual desirability yielded excellent results of 1.0000, 0.9188, 1.0000, and 0.9839 for catechin, caffeine, phenol content, and powder. The settings appear to yield functional results for entire responses. Due to the concerns in tropical skin nutrition applications, smaller particle size green tea can promote better adsorption than larger sizes.

Induction of Apoptosis via Inactivating PI3K/AKT Pathway in Colorectal Cancer Cells Using Aged Chinese Hakka Stir-Fried Green Tea Extract.

Food extract supplements, with high functional activity and low side effects, play a recognized role in the adjunctive therapy of human colorectal cancer. The present study reported a new functional beverage, which is a type of Chinese Hakka stir-fried green tea (HSGT) aged for several years. The extracts of the lyophilized powder of five HSGT samples with different aging periods were analyzed with high-performance liquid chromatography. The major components of the extract were found to include polyphenols, catechins, amino acids, catechins, gallic acid and caffeine. The tea extracts were also investigated for their therapeutic activity against human colorectal cancer cells, HT-29, an epithelial cell isolated from the primary tumor. The effect of different aging time of the tea on the anticancer potency was compared. Our results showed that, at the cellular level, all the extracts of the aged teas significantly inhibited the proliferation of HT-29 in a concentration-dependent manner. In particular, two samples prepared in 2015 (15Y, aged for 6 years) and 2019 (19Y, aged for 2 years) exhibited the highest inhibition rate for 48 h treatment (cell viability was 50% at 0.2 mg/mL). Further, all the aged tea extracts examined were able to enhance the apoptosis of HT-29 cells (apoptosis rate > 25%) and block the transition of G1/S phase (cell-cycle distribution (CSD) from <20% to >30%) population to G2/M phase (CSD from nearly 30% to nearly 10%) at 0.2 mg/mL for 24 h or 48 h. Western blotting results also showed that the tea extracts inhibited cyclin-dependent kinases 2/4 (CDK2, CDK4) and CylinB1 protein expression, as well as increased poly ADP-ribose polymerase (PRAP) expression and Bcl2-associated X (Bax)/B-cell lymphoma-2 (Bcl2) ratio. In addition, an upstream signal of one of the above proteins, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signalling, was found to be involved in the regulation, as evidenced by the inhibition of phosphorylated PI3K and AKT by the extracts of the aged tea. Therefore, our study reveals that traditional Chinese aged tea (HSGT) may inhibit colon cancer cell proliferation, cell-cycle progression and promoted apoptosis of colon cancer cells by inactivating PI3K/AKT signalling.

Pengaruh Suhu Penyeduhan dan Takaran Saji Terhadap Karakteristik Teh Hitam La Vie en Rose Produksi PT. Bali Cahaya Amerta

Black tea is tea produced from the shoots of tea leaves (Camellia sinensis) through a fermentation process. Black tea La Vie en Rose produced by PT. Bali Cahaya Amerta is one type of tea that is promoted as a functional drink or beverage with antioxidant properties. This tea consists of a mixture of black tea and rose bud. The purpose of this study was to determine the effect of brewing temperature and serving dosage on the characteristics of black tea La Vie en Rose and determine the brewing temperature and serving dosage in order to produce black tea La Vie en Rose with the best characteristics. The experiment in this study used a factorial completely randomized design with two factors as treatment, including the brewing temperature which consisted of 3 levels, namely 70o± 2oC, 80o± 2oC, 90o± 2oC and the serving dosage consisted of 4 levels, namely 2 grams, 3 grams, 4 grams and 5 grams. The observed variables were antioxidant activity IC50, extract content in water, color intensity (L*, a*, b*) and organoleptic test (hedonic test). Results showed that the interaction between the brewing temperature treatment and serving dosage very influential on the antioxidant activity of IC50, hedonic test, and yellowness level (b*) but had no effect on brightness level (L*) and redness level (a*). The best treatment was at a brewing temperature of 90oC and a serving dosage of 3 grams to produce black tea La Vie en Rose with antioxidant activity characteristics IC50 of 239,628±0,22 ppm, organoleptic test of overall acceptance 5.9±0.79 (slightly like to really like), as well as water soluble extract content of 16,5%, brightness level (L*) 19.17±0,5 , redness level (a*) 9.98±0.7, yellowness level (b*) 19.46±0,41.

Determination of four aflatoxins on dark tea infusions and aflatoxin transfers evaluation during tea brewing

In daily tea drinking, little is known on aflatoxin transfers from tea-leaf to infusion during brewing and the actual intake. A verified aflatoxins analytical method on tea infusion is significant to the exposure assessment. Here, an optimal method 3 (M3) was screened and validated on four aflatoxins (B1, B2, G1 and G2) simultaneous determination. Recoveries of AFG1 and AFB1 were 87.37 %±1.99 %-102.03 %±8.62 %, and AFG2 and AFB2 were 83.99 %±8.65 %-100.14 %±1.69 %. The correlation coefficient on the fortified samples determination was > 0.99 for each aflatoxin. In accuracy and precision validation, aflatoxins recoveries in high and low fortified samples were 85.94 %-103.83 %, and RSDs were 2.20 %-9.15 %. Method applicability test showed that the M3 was qualified for six different dark tea types. Extraction rate of 30-days stored AFB1 fortified tea-leaf by acetonitrile–water (84:16, v/v) was < 50 %; meanwhile, only 2.94 % spiked AFB1 was released by ten times tea brewing which indicated that Puerh tea have strong adsorbability to aflatoxin.

Effects of Fermentation Time and Type of Tea on the Content of Micronutrients in Kombucha Fermented Tea.

The fermented tea beverage Kombucha is obtained through a series of biochemical and enzymatic reactions carried out by symbiotic cultures of bacteria and yeasts (SCOBY). It contains organic acids, vitamins, amino acids, and biologically active compounds, notably polyphenols, derived mainly from tea. Kombucha exhibits a range of health-promoting properties, including antioxidant or detoxifying effects. This fermented beverage is traditionally brewed with black tea, but other types of tea are used increasingly, which may have significant implications in terms of chemical composition and health-promoting effects. In this preliminary study, we investigated the content of micronutrients (manganese (Mn), copper (Cu), iron (Fe), chromium (Cr) and zinc (Zn)) by the ICP-OES method in Kombucha prepared with black, red, green and white tea at different time points of fermentation (1, 7, 14 days). It should be noted that the composition of separate ingredients such as tea, leaven or sugar has not been studied. Kombucha had the highest content of zinc-0.36 mg/L to 2.08 mg/L, which accounts for between 3% and 26% of the RDA (Recommended Dietary Allowance) for adults, and the smallest amounts of chromium (0.03 mg/L to 0.09 mg/L), which however represents as much as between 75% and 232% of the RDA. It has been demonstrated that the type of tea as well as the day of fermentation have a significant effect on the concentrations of selected minerals. Kombucha can therefore supplement micronutrients in the human diet.

Effects of Preharvest Shading on Dynamic Changes in Metabolites, Gene Expression, and Enzyme Activity of Three Tea Types during Processing.

Preharvest shading significantly influences tea flavor. However, little attention has been given to the mechanism of shading on metabolites, genes, and enzymes in the processing of different tea types. Our study identified 1028 nonvolatile metabolites covering 10 subclasses using a widely targeted metabolome. The results show that shading had a greater effect on the compositions of amino acids, flavonoids, and theaflavins in tea leaves. The combined transcriptomics and enzyme activity analysis results indicate that the upregulated expression of asparagine, aspartate, and tryptophan synthesis genes and proteolytic enzymes promoted the accumulation of amino acids. The downregulated enzyme genes resulted in the reduction of nongalloylated catechins and flavonoid glycosides. Simultaneously, the accumulation of TFs in shaded tea was due to the enhanced enzymatic activities of polyphenol oxidase and peroxidase during processing. Theaflavin-3-3'-di-O-gallate was also significantly positively correlated with the antioxidant and hypoglycemic activities of shaded tea. The results contribute to a better understanding of how preharvest treatments influence summer tea quality.

PHARMACEURICAL FORMULA AND TECHNOLOGY DEVELOPMENT OF GREEN TEA GRANULES

The production of products with well-balanced biologically active compounds is one of the main tasks of the present day. The green tea raw product causes the high interest from this point of view and gives the opportunity to develop the biologically valuable product. In comparison with other types of tea, does not undergo to fermentation and keep the important useful agents. Was developed the formula of green tea granules by using the chopped raw material and its dry extract: (1) The chopped leaves of green tea- 0.5% PVP water solution (1:1); (2) The dry extract of green tea – 0.5% PVP ethanol solution (96% alcohol) (1:0.5). &nbsp;Based on the conducted studies was developed the optimal technology of green tea granules reception, which has the following flow steps: 1. Grinding; sieving (≤1mm fraction separation); mixing with the granulating agent (0.5% PVP water solution); granulation to 2 mm; Drying (at 40-50°С temperature); standardisation, packaging, labelling. 2. Extraction I (at 90°С for 0.5 hrs, in ratio 1:20); filtration I; Extraction II (at 90°С for 0.5 hrs, in ratio 1:20); filtration II; mixing (filtrate I and filtrate II); thickening; drying (at 60°С), mixing with the granulating agent (0.5% PVP ethanol solution); granulation to 2 mm; drying at room temperature; standardisation; packaging, labelling. Experimentally was determined the technological and physic-chemical properties of received granules. Established the accordance of these characteristics to the appropriate specification.