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GB 5009.31-2016 PDF in English


GB 5009.31-2016 (GB5009.31-2016) PDF English
Standard IDContents [version]USDSTEP2[PDF] delivered inName of Chinese StandardStatus
GB 5009.31-2016English90 Add to Cart 0-9 seconds. Auto-delivery. National Food Safety Standard -- Food stuffs -- Determination of p-hydroxybenzoic acid esters in food stuffs Valid
GB/T 5009.31-2003English199 Add to Cart 2 days Determination of p-hydroxybenzoic acid esters in foods Obsolete
GB 5009.31-1985English199 Add to Cart 2 days Method for determination of BHT in oils and fats Obsolete
Standards related to (historical): GB 5009.31-2016
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GB 5009.31-2016: PDF in English

GB 5009.31-2016 GB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA National Food Safety Standard - Determination of p-hydroxybenzoic acid esters in foodstuffs ISSUED ON. AUGUST 31, 2016 IMPLEMENTED ON. MARCH 1, 2017 Issued by. National Health and Family Planning Commission of the People’s Republic of China Table of Contents Foreword ... 3  1 Scope ... 4  2 Principle ... 4  3 Reagents and Materials ... 4  4 Instrument and Apparatus ... 6  5 Analysis Steps ... 6  6 Expression of Analysis Results ... 8  7 Precision ... 8  8 Others ... 8  Appendix A ... 9  6 Expression of Analysis Results ... 7  7 Precision ... 8  8 Others ... 8  Appendix A - Chromatogram of Parabens Standard Solution ... 9  Foreword This Standard replaces GB/T 5009.31-2003 "Determination of p-hydroxybenzoic acid esters in foods". Compared with GB/T 5009.31-2003, main changes in this Standard are as follows. - The Standard’s name was changed to "National Food Safety Standard - Determination of p-hydroxybenzoic acid esters in foodstuffs"; - Expand the detection range of parabens and add the detection for methyl paraben and butyl paraben; - Revise the expression for the samples’ weighing method - soy sauce, vinegar and juice - in analysis step; - Revise the standard curve range of parabens; - Gas chromatography adds analysis and measurement conditions for capillary column and deletes analysis and measurement conditions for packed column; - Add the limit of quantitation for the determination method of parabens in foods; - Modify the calculation formula. Modify the calculation basis for calculation result - from parabens to p-hydroxybenzoic acid. National Food Safety Standard - Determination of p-hydroxybenzoic acid esters in foodstuffs 1 Scope This Standard specifies the gas chromatography method for the methyl paraben, ethyl p-hydroxybenzoate, propyl paraben and butyl paraben in foods. This Standard is applicable to the determination of methyl paraben, ethyl p- hydroxybenzoate, propyl paraben and butyl paraben in soy sauce, vinegar, beverages and jams. 2 Principle After the acidification of the sample, use ethyl ether to extract the parabens, concentrate it until it closes to dryness; use ethanol to re-dissolve it; use the gas chromatography of hydrogen flame ionization detector to perform separated determination; use retention time to conduct qualitative diagnosis; use external standard method to conduct quantitative diagnosis. 3 Reagents and Materials Unless otherwise stated, all the reagents used in this method shall be the analytical purity. The water shall be the grade-II water specified in GB/T 6682. 3.1 Reagents 3.1.1 Anhydrous ether (C2H5OC2H5). Redistilled. 3.1.2 Anhydrous ethanol (C2H5OH). Guaranteed reagent. 3.1.3 Hydrochloric acid (HCl). 3.1.4 Sodium chloride (NaCl). 3.1.5 Anhydrous sodium sulfate (Na2SO4). 3.1.6 Sodium bicarbonate (NaHCO3). 3.2 Preparation of reagents 4 Instrument and Apparatus 4.1 Gas chromatograph. it is equipped with the hydrogen flame ionization detector (FID). 4.2 Balance. the sensitivity weight is 0.1 mg and 1 mg. 4.3 Rotary evaporator. 4.4 Vortex mixer. 5 Analysis Steps 5.1 Preparation for the sample 5.1.1 Processing for the sample 5.1.1.1 Soy sauce, vinegar and beverages. general liquid sample can be sampled directly after the shaking. Weigh and take 5g (accurate to 0.001g) of the sample into a small beaker; transfer it into a 125mL separating funnel; use 10mL of saturated sodium chloride solution to wash the small beakers in batch; combine the cleaning solutions in the 125mL separating funnel; add 1mL of 1.1 hydrochloric acid to perform acidification; shake it evenly; use 75mL, 50mL and 50mL of anhydrous ether to respectively extract it for three times and 2min for each time; place it for a moment; discard the water layer; combine the ether layer into the 250mL separating funnel; add 10mL of saturated sodium chloride solution to wash it for one time; respectively use 30 mL, 30 mL and 30 mL of sodium bicarbonate solution to wash it for three times; discard the water layer. Use filter paper to absorb the water at funnel’s neck; through the anhydrous sodium sulfate (about 20g), filter the organic layer into a concentrating flask; concentrate it on the rotary evaporator until it closes to dryness; use nitrogen to remove the residual solvent; accurately add 2.0 mL of anhydrous ethanol to dissolve the residues for gas chromatography. 5.1.1.2 Jam. weigh and take 5g (accurate to 0.001g) of jam sample which has been homogenized in advance in the 100mL test tube with stopper; add 1mL of 1.1 hydrochloric acid to perform acidification AND 10 mL of saturated sodium chloride solution; perform 1min~2min vortex mixing to make uniform solution; then use 50 mL, 30 mL and 30 mL of anhydrous ether to extract it for three times and 2min for each time; transfer it with the pipette into a 250mL separating funnel; add 10mL of saturated sodium chloride solution to wash it for one time; then use 30mL, 30mL and 30mL of sodium bicarbonate solution to wash it for three times; discard the water layer. Use filter paper to absorb the water on the funnel’s neck; through the anhydrous sodium sulfate (about 20g), filter the organic layer into a concentrating flask; concentrate it on the rotary evaporator until it closes to dryness; use nitrogen to remove the residual ......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.