Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard replaces "4.8 Determination of solvent residual" in "Method for Analysis of Hygienic Standard of Edible Oils" (GB/T 5009.37-2003) and "6 Determination of Solvent Residuals" in "Method for Analysis of Hygienic Standard of Edible Soybean Meal" GB/T 5009.117-2003).
Compared to the above standards, this standard has the following main changes:
——The standard name is modified to "National Food Safety Standard - Determination of Solvent Residual Quantity in Foods";
——The method for analysis of solvent residual is modified;
——The method for plotting of standard curve is modified;
——The calculation formulae for the results are modified.
National Food Safety Standard - Determination of Solvent Residue in Foods
1 Scope
This standard specifies the method for determination of solvent residual quantity in edible vegetable oil and meal for food processing.
This standard is applicable to determination of solvent residual quantity in edible vegetable oil and meal for food processing.
2 Terms and Definitions
For the purpose of this document, the following terminologies and definitions apply.
2.1 base vegetable oil
belonging to the same species with the tested sample; the refined vegetable oil obtained by refining procedure (deodorization and decoloration etc.), or the vegetable oil via ultrasonic degassing at room temperature, the solvent residual quantity of which shall be lower than the detection limit
2.2 base meal
belonging to the same species with the tested sample; the meal for food processing completely removing solvent residual through deep processing or heating in laboratory, the solvent residual quantity of which shall be lower than the detection limit
3 Principle
Solvent residuals in the sample will spread to gas phase in sealed container and dynamic balance of concentration will be achieved between gas phase and liquid phase; inspect content of the solvent residuals in upper gas phase by headspace gas chromatography, and the actual content of solvent residuals in to-be-tested sample can be calculated.
4 Reagents and Materials
Unless otherwise specified, analytical reagents and Grade 1 water specified in GB/T 6682 are used in this method.
4.1 Reagents
4.1.1 N,N-dimethyl acetamide [CH3C(O)N(CH3)2]: purity≥99%.
4.1.2 N-heptane(C7H16): purity≥99%.
4.2 Reagent preparation
Standard N-heptane working solution: accurately add 1mL of n-heptane to 10mL-volumetric flask, rapidly add N, N-dimethyl acetamide, and scale the volume to the scale.
4.3 Standard
Solvent residual standard: "No. 6 solvent" solution, concentration of 10 mg/mL and solvent of N, N-dimethyl acetamide, or standard substances approved and awarded with reference material certificate for inspection of other solvent residual.
4.4 Preparation of standard solution
4.4.1 For vegetable oil: weigh 6 portions of 5.0g (accurate to 0.01g) of base vegetable oil to 20mL headspace sample-injecting bottle, rapidly add 5μL of n-heptane standard working solution into each as internal standard (i.e. content: 68mg/kg), lightly shake up, rapidly add into 0μL, 5μL, 10μL, 25μL, 50μL and 100μL of No. 6 solvent standard by microinjector, seal and obtain base vegetable oil standard solution with concentration of 0mg/kg, 10mg/kg, 20mg/kg, 50mg/kg, 100mg/kg, and 200mg/kg. Remain headspace sample-injecting bottle to be upright, and conduct fast circular rotation on horizontal table for thorough mixing. Pay attention that the base vegetable oil cannot contact sealing gasket during rotation, otherwise, re-prepare it.
4.4.2 For meal: weigh 6 portions of 3.0g (accurate to 0.01g) of base vegetable oil to 20mL headspace sample-injecting bottle, then add into 400μL of water for each bottle, and rapidly add 0μL, 3μL, 9μL, 15μL, 30μL and 150μL of No. 6 solvent standard by microinjector, seal and obtain base meal standard solution with concentration of 0mg/kg, 10mg/kg, 30mg/kg, 50mg/kg, 100mg/kg, and 500mg/kg. Remain headspace sample-injecting bottle to be upright, and conduct fast circular rotation on horizontal table for thorough mixing. Pay attention that the base meal cannot contact sealing gasket during rotation, otherwise, re-prepare it.
5 Apparatus and Equipment
5.1 Gas chromatograph: equipped with hydrogen flame ionization detector.
5.2 Headspace bottle: 20mL, equipped with aluminum cap and butyl rubber or silicon resin glue isolation pad free of hydrocarbon solvent residual.
5.3 Analytical balance: with sensibility of 0.01g.
5.4 Microinjector: 10μL, 25μL, 50μL, 100μL, 250μL and 500μL.
5.5 Ultrasonic vibrator.
5.6 Blast oven.
5.7 Thermostatic oscillator.
6 Analysis Procedures
6.1 Sample preparation
6.1.1 Preparation of vegetable oil sample: weigh 5g (accurate to 0.01g) of vegetable oil sample, place at 20mL headspace sample-injecting bottle, rapidly add into 5μL of n-heptane standard working solution as internal standard, slightly shake up by hand and seal. Remain the headspace sample-injecting bottle upright to be analyzed. Pay attention that the vegetable oil sample cannot contact sealing gasket during rotation, otherwise, re-prepare it.
6.1.2 Preparation of meal sample: weigh 3g (accurate to 0.01g) of meal sample, place at 20mL headspace sample-injecting bottle, add into 400μL of deionized water and seal it. Remain the headspace sample-injecting bottle upright to be analyzed. Pay attention that the base meal cannot contact sealing gasket during preparation, otherwise, re-prepare it.
Foreword i
1 Scope
2 Terms and Definitions
3 Principle
4 Reagents and Materials
5 Apparatus and Equipment
6 Analysis Procedures
7 Expression of Analysis Result
8 Precision
9 Others
Appendix A Gas chromatogram for No. 6 Solvent Standard
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard replaces "4.8 Determination of solvent residual" in "Method for Analysis of Hygienic Standard of Edible Oils" (GB/T 5009.37-2003) and "6 Determination of Solvent Residuals" in "Method for Analysis of Hygienic Standard of Edible Soybean Meal" GB/T 5009.117-2003).
Compared to the above standards, this standard has the following main changes:
——The standard name is modified to "National Food Safety Standard - Determination of Solvent Residual Quantity in Foods";
——The method for analysis of solvent residual is modified;
——The method for plotting of standard curve is modified;
——The calculation formulae for the results are modified.
National Food Safety Standard - Determination of Solvent Residue in Foods
1 Scope
This standard specifies the method for determination of solvent residual quantity in edible vegetable oil and meal for food processing.
This standard is applicable to determination of solvent residual quantity in edible vegetable oil and meal for food processing.
2 Terms and Definitions
For the purpose of this document, the following terminologies and definitions apply.
2.1 base vegetable oil
belonging to the same species with the tested sample; the refined vegetable oil obtained by refining procedure (deodorization and decoloration etc.), or the vegetable oil via ultrasonic degassing at room temperature, the solvent residual quantity of which shall be lower than the detection limit
2.2 base meal
belonging to the same species with the tested sample; the meal for food processing completely removing solvent residual through deep processing or heating in laboratory, the solvent residual quantity of which shall be lower than the detection limit
3 Principle
Solvent residuals in the sample will spread to gas phase in sealed container and dynamic balance of concentration will be achieved between gas phase and liquid phase; inspect content of the solvent residuals in upper gas phase by headspace gas chromatography, and the actual content of solvent residuals in to-be-tested sample can be calculated.
4 Reagents and Materials
Unless otherwise specified, analytical reagents and Grade 1 water specified in GB/T 6682 are used in this method.
4.1 Reagents
4.1.1 N,N-dimethyl acetamide [CH3C(O)N(CH3)2]: purity≥99%.
4.1.2 N-heptane(C7H16): purity≥99%.
4.2 Reagent preparation
Standard N-heptane working solution: accurately add 1mL of n-heptane to 10mL-volumetric flask, rapidly add N, N-dimethyl acetamide, and scale the volume to the scale.
4.3 Standard
Solvent residual standard: "No. 6 solvent" solution, concentration of 10 mg/mL and solvent of N, N-dimethyl acetamide, or standard substances approved and awarded with reference material certificate for inspection of other solvent residual.
4.4 Preparation of standard solution
4.4.1 For vegetable oil: weigh 6 portions of 5.0g (accurate to 0.01g) of base vegetable oil to 20mL headspace sample-injecting bottle, rapidly add 5μL of n-heptane standard working solution into each as internal standard (i.e. content: 68mg/kg), lightly shake up, rapidly add into 0μL, 5μL, 10μL, 25μL, 50μL and 100μL of No. 6 solvent standard by microinjector, seal and obtain base vegetable oil standard solution with concentration of 0mg/kg, 10mg/kg, 20mg/kg, 50mg/kg, 100mg/kg, and 200mg/kg. Remain headspace sample-injecting bottle to be upright, and conduct fast circular rotation on horizontal table for thorough mixing. Pay attention that the base vegetable oil cannot contact sealing gasket during rotation, otherwise, re-prepare it.
4.4.2 For meal: weigh 6 portions of 3.0g (accurate to 0.01g) of base vegetable oil to 20mL headspace sample-injecting bottle, then add into 400μL of water for each bottle, and rapidly add 0μL, 3μL, 9μL, 15μL, 30μL and 150μL of No. 6 solvent standard by microinjector, seal and obtain base meal standard solution with concentration of 0mg/kg, 10mg/kg, 30mg/kg, 50mg/kg, 100mg/kg, and 500mg/kg. Remain headspace sample-injecting bottle to be upright, and conduct fast circular rotation on horizontal table for thorough mixing. Pay attention that the base meal cannot contact sealing gasket during rotation, otherwise, re-prepare it.
5 Apparatus and Equipment
5.1 Gas chromatograph: equipped with hydrogen flame ionization detector.
5.2 Headspace bottle: 20mL, equipped with aluminum cap and butyl rubber or silicon resin glue isolation pad free of hydrocarbon solvent residual.
5.3 Analytical balance: with sensibility of 0.01g.
5.4 Microinjector: 10μL, 25μL, 50μL, 100μL, 250μL and 500μL.
5.5 Ultrasonic vibrator.
5.6 Blast oven.
5.7 Thermostatic oscillator.
6 Analysis Procedures
6.1 Sample preparation
6.1.1 Preparation of vegetable oil sample: weigh 5g (accurate to 0.01g) of vegetable oil sample, place at 20mL headspace sample-injecting bottle, rapidly add into 5μL of n-heptane standard working solution as internal standard, slightly shake up by hand and seal. Remain the headspace sample-injecting bottle upright to be analyzed. Pay attention that the vegetable oil sample cannot contact sealing gasket during rotation, otherwise, re-prepare it.
6.1.2 Preparation of meal sample: weigh 3g (accurate to 0.01g) of meal sample, place at 20mL headspace sample-injecting bottle, add into 400μL of deionized water and seal it. Remain the headspace sample-injecting bottle upright to be analyzed. Pay attention that the base meal cannot contact sealing gasket during preparation, otherwise, re-prepare it.
Contents of GB 5009.262-2016
Foreword i
1 Scope
2 Terms and Definitions
3 Principle
4 Reagents and Materials
5 Apparatus and Equipment
6 Analysis Procedures
7 Expression of Analysis Result
8 Precision
9 Others
Appendix A Gas chromatogram for No. 6 Solvent Standard
