PENGARUH UMUR DAUN TEH DAN WAKTU OKSIDASI ENZIMATIS TERHADAP KANDUNGAN TOTAL FLAVONOID PADA TEH HITAM (Camellia sinesis)

Flavonoid compound is an important compound of tea products. However, the flavonoid level content in black tea is lowest than other teas. This is due to the processing of black tea which has an enzymatic oxidation stage and the tea age leaves when picking. Young tea leaves contain higher total flavonoids than old tea leaves. With an average level of total flavonoids, the young tea leaves is 27.76% qe w / w, while for the old tea leaves 18.61% qe w / w. However, the enzymatic oxidation time treatment did not affect the total flavonoids because the process only affected the quality of black tea steeping, on it’s colour, aroma, and taste. Keywords: age of tea leaves, black tea, enzymatic oxidation, total flavonoids

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KANDUNGAN SENYAWA FLAVONOID PADA DAUN MELINJO (Gnetum gnemon L.) BERDASARKAN PERBEDAAN TEMPAT TUMBUH

Biopendix: Jurnal Biologi, Pendidikan dan Terapan ◽

10.30598/biopendixvol3issue2page142-147 ◽

2017 ◽

Vol 3 (2) ◽

pp. 142-147

Author(s):

Mersy T Tanamal ◽

Pamella Mercy Papilaya ◽

Alwi Smith

Keyword(s):

Natural Resources ◽

Total Flavonoid ◽

Flavonoid Compound ◽

Total Flavonoids ◽

Total Flavonoid Content ◽

Flavonoid Content ◽

Gnetum Gnemon ◽

The Village

Background: The village of Latuhalat and Kayu Putih village is a place that is on the beach and in the mountains. Potential natural resources are quite a lot of plants melinjo (Gnetum gnemon L). This study aims to determine the total compound of flavonoid content of leaf melinjo (Gnetum gnemon L) based on place difference. Method: The method used in this study using the method of Chang et al. The solvent used for diluting the melinjo extract was methanol solvent, then measured using a UV-VIS spectrophotometer. Result: Result of analysis of flavonoid compound content, Latuhalat Village has average total flavonoid content of13.080% and average total flavonoid content in Kayu Putih Village equal to 17.028%. Kayu Putih Village has more flavonoid compound than Latuhalat Village. Conclusion: Total levels of melinjo leaf flavonoids (Gnetum gnemon L) in Kayu Putih Village were more than total flavonoids of leaf melinjo (Gnetum gnemon L) in Latuhalat Village.

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Changes in Phytochemicals and Determination of Optimum Fermentation Time during Black Tea Manufacturing

Journal of Scientific Research ◽

10.3329/jsr.v12i4.45452 ◽

2020 ◽

Vol 12 (4) ◽

pp. 657-664

Author(s):

M. M. Rahman ◽

M. M. Hossain ◽

R. Das ◽

I. Ahmad

Keyword(s):

Black Tea ◽

Quality Parameters ◽

Biochemical Changes ◽

Enzymatic Oxidation ◽

Time Intervals ◽

Fermentation Time ◽

Tea Quality ◽

Processing Steps

Black tea processing consists of four steps, namely withering, CTC, fermentation and drying, while cup quality made tea mostly controlled by fermentation step. This study evaluated biochemical changes at different stages of black tea processing in Bangladesh and determined the optimum fermentation time. Samples were collected from different tea processing stages to measure major phytochemicals and time intervals during fermentation to measure theaflavins and thearubigins ratio. Caffeine content was the least susceptible to processing steps. Biochemical changes started at withering, cell maceration and enzymatic oxidation started at CTC processing, thus the major reduction in the reducing sugar (20.46 to 04.95 ppm), catechin (16.88 to 7.95 ppm) and polyphenol (42.30 to 30.73 ppm) occurred here. The significant changes appeared during fermentation when polyphenol content decreased from 44.66 to 18.23 and catechin from 17.41 to 03.98 ppm due to the breakdown of these compounds to theaflavins (TF) and thearubigins (TR). The TF and TR ratio increased with fermentation time, and the highest of 1:8.4 was found at 50 min, which turned into 1:10 in the final product. The made tea quality parameters were comparable or better at fermentation time of 50 min than the quality of the black tea available in market.

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Impact of the mosquito bug (Helopeltis theivora) infestation on the quality of tea (Camellia sinensis)

Bangladesh Journal of Zoology ◽

10.3329/bjz.v44i2.32759 ◽

2017 ◽

Vol 44 (2) ◽

pp. 197-207 ◽

Cited By ~ 1

Author(s):

Razia Sultana Chowdhury ◽

Irin Siddiqua Moly ◽

Mainuddin Ahmed ◽

Mohammad Shameem Al Mamun ◽

Md Mozammel Hoque ◽

...

Keyword(s):

Black Tea ◽

Quality Parameters ◽

Physiological Parameters ◽

Lower Amount ◽

Tea Leaves ◽

Helopeltis Theivora ◽

Tea Mosquito Bug ◽

Chlorophyll A And B ◽

Physiological And Biochemical

The influence of tea mosquito bug (Helopeltis theivora) infestation on the physiological and biochemical changes in tea leaves as well as quality parameters of the made tea was investigated. Results revealed that physiological parameters such as polyphenol, chlorophyll a and b, carotenoids, catechins, reducing sugar and antioxidant activity reduced when the shoots are infested by tea mosquito bug. Black tea prepared from Helopeltis infested shoots contained significantly lower amount of theaflavin and thearubigin ratio, highly polymerized substances, total liquor colour, colour index, caffeine and lipid than that of uninfested fresh tea leaves. The infestation of tea mosquito bug significantly reduced the physiological parameters of tea leaves and quality parameters of made tea that hamper the quality of drinking tea.Bangladesh J. Zool. 44(2): 197-207, 2016

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Absolute Quantitative Volatile Measurement from Fresh Tea Leaves and the Derived Teas Revealed Contributions of Postharvest Synthesis of Endogenous Volatiles for the Aroma Quality of Made Teas

Applied Sciences ◽

10.3390/app11020613 ◽

2021 ◽

Vol 11 (2) ◽

pp. 613

Author(s):

Mingjie Chen ◽

Li Guo ◽

Huiwen Zhou ◽

Yaling Guo ◽

Yi Zhang ◽

...

Keyword(s):

Black Tea ◽

Significant Loss ◽

Tea Leaves ◽

Gene Expressions ◽

Flame Ionization ◽

Tea Quality ◽

Different Types ◽

Aroma Characteristics ◽

Volatile Profiles

Characteristic aroma is a well-appreciated feature contributing to tea quality. Although extensive studies have been made to investigate aroma biosynthesis and gene expressions during tea making processes, it remains unclear whether the endogenous volatile biosynthesis during postharvest tea processing contributes to the aroma quality of made tea. To critically evaluate this question, we used the same batch of fresh tea leaves and produced three different types of tea with different degrees of fermentation (green tea, oolong tea, and black tea). Total volatiles were extracted by solvent-assisted-flavor evaporation, then quantified by gas chromatography-flame ionization detector combined with response factor correction for quantitative measurement. Compared with fresh tea leaves, the volatile profiles of the made teas were dramatically altered, with significant loss for the majority of endogenous volatiles and simultaneous gain for non-endogenous volatiles. By calculation of odor-activity values, the potential volatiles contributing to the aroma characteristics of each tea type were identified. Our data suggest that postharvest synthesis of endogenous volatiles did not contribute to the aroma quality of made tea.

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Effect of Fermentation Conditions and Plucking Standards of Tea Leaves on the Chemical Components and Sensory Quality of Fermented Juice

Journal of Chemistry ◽

10.1155/2018/4312875 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Ping Tang ◽

Dan-Yu Shen ◽

Yong-Quan Xu ◽

Xing-Cai Zhang ◽

John Shi ◽

...

Keyword(s):

Sensory Quality ◽

Black Tea ◽

Chemical Components ◽

Tea Leaves ◽

Time Duration ◽

Essential Information ◽

Fermentation Conditions ◽

Overall Acceptability ◽

Fermented Juice

The effects of fermentation conditions (temperature, time, and pH) and plucking standards (one leaf and a bud to four leaves and a bud) on the chemical components and sensory quality of the fermented juices processed from crushed fresh tea leaves were investigated. The results showed that optimum fermentation conditions that resulted in fermented juices of the best sensory quality and the highest content of TFs were a temperature of 35°C, time duration of 75 min, and pH 5.1. The fermented juices processed from new shoots with three leaves and a bud or four leaves and a bud afforded high overall acceptability and TF concentration. These differences arise because tea leaves with different plucking standards have different catechin content and enzyme activities. Fermented tea juice possessed higher concentrations of chemical components such as soluble solids, amino acids, and TFs and exhibited better sensory quality as compared to black tea infusion. The TF concentrations decreased as the pH of the fermenting juice increased, and the fermented juice showed the best overall acceptability. These results provide essential information for the improvement of the processing of black tea beverage by suggesting fermentation of fresh tea leaves as a better alternative to their infusion.

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Enhancement of Black Tea Aroma by Adding the β-Glucosidase Enzyme during Fermentation on Black Tea Processing

International Journal of Food Science ◽

10.1155/2021/5542109 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Supriyadi Supriyadi ◽

Alfrista Ruri Nareswari ◽

Aprilia Fitriani ◽

Rachmad Gunadi

Keyword(s):

Volatile Compound ◽

Methyl Salicylate ◽

Sodium Citrate ◽

Black Tea ◽

Tea Leaves ◽

Citrate Buffer ◽

Sodium Citrate Buffer

Black tea aroma is one of the essential attributes in determining the quality of black tea. β-Glucosidases were investigated for their ability to enhance the aroma of black tea by hydrolyzing the glycoside compound. The addition of β-glucosidase was done by dissolving the enzyme on a sodium citrate buffer (pH 5.0), which was then sprayed on tea leaves during black tea processing. The β-glucosidase treatment significantly increases the volatile compound from glycoside precursors such as linalool, geraniol, and methyl salicylate. Moreover, the volatile compound from carotenoid and lipid precursors (nerolidol and β-cyclocitral) was also increased with β-glucosidase treatment.

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Effects of withering on the main physical properties of withered tea leaves and the sensory quality of congou black tea

Journal of Texture Studies ◽

10.1111/jtxs.12498 ◽

2019 ◽

Vol 51 (3) ◽

pp. 542-553

Author(s):

Yulong Ye ◽

Chunwang Dong ◽

Fan Luo ◽

Jilai Cui ◽

Xueli Liao ◽

...

Keyword(s):

Physical Properties ◽

Sensory Quality ◽

Black Tea ◽

Tea Leaves

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Screening tea hybrid with abundant anthocyanins and investigating the effect of tea processing on foliar anthocyanins in tea

Folia Horticulturae ◽

10.2478/fhort-2020-0025 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Jian-Guang Hu ◽

Long-Jie Zhang ◽

Yue-Yue Sheng ◽

Kai-Rong Wang ◽

Yun-Long Shi ◽

...

Keyword(s):

Green Tea ◽

Marked Decrease ◽

Female Parent ◽

Black Tea ◽

Field Investigation ◽

Tea Leaves ◽

Leaf Yield ◽

High Level ◽

Tea Cultivar

AbstractAnthocyanins are important bioactive supplements that are consumed from multiple foods and beverage products. Screening tea cultivars producing a high level of anthocyanins can help to enrich the edible bioactive supplements. ‘Zijuan’ (ZJ) is a tea cultivar growing purple shoots rich in anthocyanins, but it is susceptible to freezing winter and sprouts late in spring. Hybridisation using ‘ZJ’ as the female parent and an early sprouting cultivar ‘Wuniuzao’ as the male parent was carried out, and four hybrids with purple leaves were obtained. The quality of anthocyanins, catechins, caffeine and amino acids in shoots with three leaves and a bud of the purple leaf hybrids obtained were determined based on the field investigation on sprouting time in spring, winter resistance and leaf yield. It showed that hybrid ‘B-2’ sprouted earlier in the spring, contained a higher level of anthocyanins and also showed good performance in winter resistance than its female parent ‘ZJ’. It also showed that black tea processing induced a marked decrease in foliar anthocyanins, but green tea processing had little effect on the foliar anthocyanins. Purple tea leaves should be prepared into unfermented green tea instead of fermented black tea to preserve the high level of anthocyanins in the final tea products.

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Total Polyphenol, Rehydration Ratio, and Liquor Color of Different Grade Green Tea

Jurnal Ilmu Pangan dan Hasil Pertanian ◽

10.26877/jiphp.v3i2.5116 ◽

2020 ◽

Vol 3 (2) ◽

pp. 159-169

Author(s):

M Iqbal Prawira-Atmaja ◽

Beauty Azhary ◽

Sugeng Harianto ◽

Hilman Maulana ◽

Shabri Shabri ◽

...

Keyword(s):

Green Tea ◽

Alcoholic Beverage ◽

Black Tea ◽

Enzymatic Oxidation ◽

Rehydration Ratio ◽

Total Polyphenols ◽

Potential Health ◽

Total Polyphenol ◽

Practice Gap

Tea is a non-alcoholic beverage that is widely consumed after water with potential health benefits. In general, tea processing divided into three types, non-enzymatic oxidation process (green tea), semi-oxidation (oolong tea), and with enzymatic oxidation (black tea). The sorting and grading is a stage in controlling the quality of green tea. This study aims to determine the characteristics of different grades of green tea on the total polyphenols, liquor color, and rehydration ratio. The results showed that the pekoe/pecco grade had the highest total polyphenol and rehydration ratio compared to other grades. Pekoe grade has a greenish yellow and brighter liquor color. Application of good agriculture practice (GAP) and plucking of fresh tea leaves should be considered to obtain more grade pekoe in the green tea processing.

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