GB 5009.264-2016 PDF in English
GB 5009.264-2016 (GB5009.264-2016) PDF English
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Determination of benzyl acetate in tea-drink -- Gas chromatography method
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Standards related to: GB 5009.264-2016
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GB 5009.264-2016: PDF in English GB 5009.264-2016
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
National food safety standard -
Determination of benzyl acetate in food
ISSUED ON. DECEMBER 23, 2016
IMPLEMENTED ON. JUNE 23, 2017
Issued by. National Health and Family Planning Commission of the PRC;
China Food and Drug Administration
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Principle ... 4
3 Reagents and materials ... 4
4 Instruments and equipment... 5
5 Analytical procedures ... 5
6 Expression of analytical results ... 6
7 Precision ... 7
8 Others ... 7
Appendix A Chromatogram of benzyl acetate of different concentrations added
to blank tea-drink ... 8
National food safety standard -
Determination of benzyl acetate in food
1 Scope
This standard specifies the gas chromatographic method for the determination
of benzyl acetate in tea-drink.
This standard applies to the determination of benzyl acetate in tea-drink.
2 Principle
After the benzyl acetate in the tea-drink is extracted and made to certain volume,
it is separated from the internal standard n-dodecane and other components in
a gas chromatographic column, detected by a hydrogen flame ionization
detector, quantified by an internal standard method.
3 Reagents and materials
Unless otherwise stated, the reagents used in this method are of analytical
grade, the water is the grade III water as specified in GB/T 6682.
3.1 Reagents
3.1.1 Dichloromethane (CH2Cl2).
3.1.2 Anhydrous ethanol (C2H6O).
3.2 Standard substance
3.2.1 Benzyl acetate (C9H10O2). Content ≥ 98%.
3.2.2 n-Dodecane [CH3(CH2)10CH3]. Content ≥ 98%.
3.3 Preparation of standard solution
3.3.1 Benzyl acetate standard stock solution (1000 μg/mL). Accurately WEIGH
100 mg (accurate to 0.1 mg) of benzyl acetate; USE absolute ethanol to
dissolve and dilute it to 100 mL.
3.3.2 Benzyl acetate use solution (80 μg/mL). Accurately TAKE 8.00 mL of 1000
μg/mL benzyl acetate solution; USE dichloromethane to make its volume reach
to 100 mL. PREPARE it before use.
3.3.3 n-Dodecane internal standard solution (200 μg/mL). Accurately WEIGH
20 mg (accurate to 0.1 mg) of n-dodecane; USE dichloromethane to dilute it to
100 mL.
3.3.4 Preparation of mixed standard solution. ADD 4 mL of 80 μg/mL benzyl
acetate and 1 mL of 200 μg/mL n-dodecane solution into a 5 mL colorimetric
tube; MIX it uniformly; it is used to calculate the relative correction factor.
4 Instruments and equipment
4.1 Gas Chromatograph. It is equipped with a hydrogen flame ionization
detector.
4.2 Nitrogen blow dryer.
4.3 Analytical balance. The sensitivities are 0.1 mg and 0.01 g.
5 Analytical procedures
5.1 Pretreatment of sample
Accurately WEIGH 40 g (accurate to 0.01 g) of tea-drink in a 125 mL separatory
funnel; ADD 20 mL of dichloromethane; SHAKE it for 1 min; LET it be standing
for layering; DROP the dichloromethane layer slowly into the funnel (a little
cotton wool at the bottom, 10 g anhydrous sodium sulfate above it) to perform
dehydration and filtration; COLLECT it into a 50 mL graduated test tube; then
ADD 20 mL of dichloromethane into the separatory funnel; SHAKE it for 1 min;
LET it be standing for layering; PERFORM filtration and collection as above;
then USE a small amount of dichloromethane to rinse the funnel for 3 times;
COLLECT it. USE nitrogen blow dryer (30 °C) to concentrate the collected
solution to about 3 mL; USE a small amount of dichloromethane to completely
transfer it into a 5 mL colorimetric tube. After adding 1 mL of 200 μg/mL n-
dodecane, USE the dichloromethane to make its volume reach to 5 mL; MIX it
uniformly to prepare for determination.
5.2 Reference conditions for gas chromatography
5.2.1 Chromatography column. SE-30 column, the column length is 30 m, the
inner diameter is 0.53 mm, the film thickness is 1.0 μm, or others of equivalent
performance.
5.2.2 Column temperature. The initial temperature is 90 °C. It is maintained at
constant temperature 1 min, then subjected to programmed temperature-rise at
the rate of 10 °C/min, the final temperature is 180 °C, which is kept for 3 min.
...... Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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