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GB/T 23193-2017 English PDF

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GB/T 23193-2017: Determination of theanine in tea -- Using high performance liquid chromatography
Status: Valid

GB/T 23193: Evolution and historical versions

Standard IDContents [version]USDSTEP2[PDF] delivered inStandard Title (Description)StatusPDF
GB/T 23193-2017English119 Add to Cart 3 days [Need to translate] Determination of theanine in tea -- Using high performance liquid chromatography Valid GB/T 23193-2017
GB/T 23193-2008English239 Add to Cart 3 days [Need to translate] Determination of theanine in tea -- High performance liquid chromatography Obsolete GB/T 23193-2008

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Basic data

Standard ID GB/T 23193-2017 (GB/T23193-2017)
Description (Translated English) Determination of theanine in tea -- Using high performance liquid chromatography
Sector / Industry National Standard (Recommended)
Classification of Chinese Standard X55
Classification of International Standard 67.140.10
Word Count Estimation 6,636
Date of Issue 2017-11-01
Date of Implementation 2018-05-01
Older Standard (superseded by this standard) GB/T 23193-2008
Regulation (derived from) National Standard Announcement 2017 No. 29
Issuing agency(ies) General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China

GB/T 23193-2017: Determination of theanine in tea -- Using high performance liquid chromatography

---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
Determination of theanine in tea-Using high performance liquid chromatography ICS 67.140.10 X55 National Standards of People's Republic of China Replacing GB/T 23193-2008 Determination of theanine in tea by high performance liquid chromatography chromatography Posted.2017-11-01 2018-05-01 implementation General Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China China National Standardization Administration released

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009. This standard replaces GB/T 23193-2008 "Determination of theanine in tea high performance liquid chromatography." And GB/T 23193- Compared to.2008, the main technical differences are as follows. --- Measuring principle and pre-treatment process is completely different; --- Sample handling differences .0.5g sample water 100mL, 80 ℃ water bath leaching 45min, modified to 1.0g sample plus boiling water 100mL, extraction 30min; --- No purification and derivatization steps, after 0.45μm membrane, direct injection. This standard is proposed by the China Federation of Supply and Marketing Cooperatives. This standard by the National Tea Standardization Technical Committee (SAC/TC339) centralized. This standard was drafted unit. China National Federation of Supply and Marketing Cooperatives Hangzhou Tea Research Institute, the National Tea Quality Supervision and Inspection Center, the National Food Quality and Safety Supervision and Inspection Center, Quanzhou Exit Inspection and Quarantine Bureau Integrated Technology Service Center, Fujian Rizhao Industrial Co., Ltd. The drafters of this standard. Zhou Weilong, Xu Jianfeng, Liu Xiaoli, Lu Xiaolei, Shi Weini, Ye Meijun, Liu Xiangzhen, Huang Guanshui, Wang Qican. This standard replaces the standards previously issued as. --- GB/T 23193-2008. Determination of theanine in tea by high performance liquid chromatography

1 Scope

This standard specifies the method for the determination of theanine content in tea by high performance liquid chromatography. This standard applies to the determination of theanine in tea.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version applies to this article Pieces. For undated references, the latest edition (including all amendments) applies to this document. GB/T 6682 analytical laboratory water specifications and test methods GB/T 8302 tea sampling Preparation of GB/T 8303 tea ground sample and determination of its dry matter content

3 principle

The theanine in tea samples was extracted by boiling water. After purifying, the RP-18 column was used to separate the strong polar compounds. The detection wavelength 210nm, measured by high performance liquid chromatography, compared with the standard series of qualitative, quantitative.

4 reagent

4.1 Unless otherwise indicated, the reagents used in the analysis were of analytical grade, water for the three water GB/T 6682 regulations. 4.2 Acetonitrile. Chromatography grade. 4.3 Theanine standard (L-theanine). Purity ≥ 99%. 4.4 HPLC mobile phase 4.4.1 Mobile phase A.100% pure water. 4.4.2 Mobile phase B, 100% acetonitrile (4.2). 4.5 Theanine standard stock solution 4.5.1 Theanine standard stock solution Weigh 0.05g Theanine (accurate to 0.0001g), dissolved in water and then transferred to 50mL volumetric flask, diluted to the mark, mix, the solution Liquid contains 1 mg of theanine per ml. Valid for one year. 4.5.2 Theanine standard liquid Respectively accurately draw Theanine standard stock solution (4.5.1) 0.0mL, 0.1mL, 0.2mL, 0.5mL, 1.0mL, 1.5mL, 2.0mL, the volume of water to 10mL to give concentrations of 0.0mg/mL, 0.01mg/mL, 0.02mg/mL, 0.05mg/mL, 0.10 mg/mL, 0.15 mg/mL, 0.20 mg/mL of the theanine standard solution. Valid for one year. 4.6 0.45μm aqueous filter.

5 instruments

5.1 High performance liquid chromatography with gradient elution, UV detector and chromatography workstation.

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