Skip to product information
1 of 7

PayPal, credit cards. Download editable-PDF & invoice in 1 second!

GB 31604.33-2016 English PDF (GB31604.33-2016)

GB 31604.33-2016 English PDF (GB31604.33-2016)

Regular price $70.00 USD
Regular price Sale price $70.00 USD
Sale Sold out
Shipping calculated at checkout.
Quotation: In 1-minute, 24-hr self-service. Click here GB 31604.33-2016 to get it for Purchase Approval, Bank TT...

GB 31604.33-2016: National Food Safety Standard -- Food Contact Materials and Articles -- Determination of Migration of Nickel

This standard specifies determination method of caprolactam and migration quantity in food contact aterials and products. This standard applies to determination of caprolactam and migration quantity in food contact materials and products.
GB 31604.33-2016
GB
NATIONAL STANDARD OF THE
PEOPLE REPUBLIC OF CHINA
National food safety standard -
Food contact materials and products
Determination of nickel migration
ISSUED ON. OCTOBER 19, 2016
IMPLEMENTED ON. APRIL 19, 2017
Issued by. National Health and Family Planning Commission of the
PEOPLE Republic of China
Table of Contents
Foreword . 3
1 Scope .. 4
2 Principle . 4
3 Reagents and materials . 4
4 Instruments and equipment .. 6
5 Analysis procedure .. 6
6 Expression of analysis results .. 7
7 Precision . 7
8 Others . 7
9 Principle . 7
10 Reagents and materials . 8
11 Instruments and equipment .. 10
12 Analysis procedure . 10
13 Expression of analysis results . 11
14 Precision . 11
15 Others . 11
Annex A Reference temperature rise program of graphite furnace atomic
absorption spectrometer . 12
Foreword
This Standard replaces the determination method for nickel migration in GB/T 5009.81-2003 ?€?Method for analysis of hygienic standard of stainless steel food containers and table wares?€? and SN/T 2829-2011 ?€?Food contact materials for export - Metal materials - Determination of migrant heavy metals in food simulant - Inductively coupled plasma atomic emission spectrometric method?€?. Compared with the determination method for nickel in GB/T 5009.81-2003, the main changes are as follows.
- MODIFY the standard name TO ?€?National food safety standard - Food
contact materials and products - Determination of nickel migration?€?;
- ADD Inductively coupled plasma mass spectrometry and inductively
coupled plasma atomic emission spectrometry.
National food safety standard -
Food contact materials and products
Determination of nickel migration
1 Scope
This Standard specifies the graphite furnace atomic absorption spectrometry, inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission spectrometry and spectrophotometric method using
dimethylglyoxime for the determination of nickel migration in food contact materials and products after being soaked in food simulants.
This Standard applies to the determination of nickel migration in food contact materials and products.
Method I -- Graphite furnace atomic absorption spectrometry
2 Principle
Use food simulants to soak parts of food contact materials and products that are expected to come in contact with foods. The soaking solution is atomized in a graphite furnace. The absorbance measured at 232.0 nm is proportional to the nickel content within a certain concentration range, which is compared with the standard series to quantify.
3 Reagents and materials
Unless otherwise stated, the reagents used in this method are all guarantee reagents, and the water is grade-2 water specified in GB/T 6682.
3.1 Reagents
3.1.1 Nitric acid (HNO3).
3.1.2 Ammonium dihydrogen phosphate (NH4H2PO4).
3.1.3 Reagents for preparing food simulants. According to specifications of GB 31604.1.
4 Instruments and equipment
NOTE. All glassware must be soaked in nitric acid solution (1 + 5) overnight and rinsed with water for later use.
4.1 Atomic absorption spectrometer. equipped with graphite furnace atomizer, nickel hollow cathode lamp.
4.2 Analytical balance. with a division of 0.1 mg.
5 Analysis procedure
5.1 Pretreatment of samples
According to the expected use and the use conditions of the sample to be tested, carry out the migration test in accordance with the migration test methods and test conditions specified in GB 5009.156 and GB 31604.1. After the soaking solution is thoroughly mixed, take part of the soaking solution for analysis. If the soaking solution is neutral or alkaline, add an appropriate amount of nitric acid so that the concentration of nitric acid in the test solution is about 5 % (volume fraction). At the same time carry out the sample blank test.
5.2 Determination
5.2.1 Instrument test conditions
Instrument reference conditions are shown in Table A.1.
5.2.2 Plotting of standard curves
PIPETTE 10 ??L of nickel standard solution and 5 ??L of ammonium dihydrogen phosphate solution (20 g/L) (the optimal injection volume may be determined in accordance with the instrument used) in the order of concentration from low to high, INJECT them into the graphite furnace at the same time. After
atomization, MEASURE the absorbance value. Take the concentrations of the standard series as the abscissa and take the corresponding absorbance values as the ordinate to plot the standard curve.
5.2.3 Determination of samples
Under the same test conditions as those for the determination of standard solution, PIPETTE 10 ??L of sample solution and 5 ??L of ammonium dihydrogen phosphate solution (20 g/L) (the optimal injection volume may be determined in accordance with the instrument used), INJECT them into the graphite furnace at the same time. After atomization, MEASURE the absorbance value.
ammonia to decolorize, then reacts with basic dimethylglyoxime to form red complexes, which are compared with the standard series to quantify.
10 Reagents and materials
Unless otherwise stated, the reagents used in this method are all analytical reagents, the water is the grade-3 water specified in GB/T 6682.
10.1 Reagents
10.1.1 Diammonium hydrogen nitrite [(NH4)2HC6H5O7].
10.1.2 Dimethylglyoxime [(CH3)2C2(NOH)2].
10.1.3 Ethanol (C2H5OH).
10.1.4 Chloroform (CHCl3).
10.1.5 Bromine Water (Br2).
10.1.6 Sodium hydroxide (NaOH).
10.1.7 Hydrochloric acid (HCl).
10.1.8 Ammonia (NH3 ?? H2O).
10.1.9 Nitric acid (HNO3). excellent regent.
10.1.10 Reagents for preparing food simulants. according to the specifications of GB 31604.1.
10.2 Preparation of reagents
10.2.1 Diammonium hydrogen nitrite solution (100 g/L). WEIGH 10 g of
diammonium hydrogen nitrite and DISSOLVE in water to 100 mL.
10.2.2 Ethanol solution (95 + 5). ADD 5 mL of water to 95 mL of ethanol, MIX well.
10.2.3 Dimethylglyoxime ethanol solution (10 g/L). DISSOLVE 1 g of
dimethylglyoxime and DISSOLVE in 100 mL of ethanol solution (95 + 5), MIX well. If there is any insoluble material, filter and the filtrate is for later use. 10.2.4 Sodium hydroxide solution (0.2 mol/L). DISSOLVE 1.0 g of sodium
hydroxide in 125 mL of water.
10.2.5 Basic dimethylglyoxime solution (10 g/L). WEIGH 1 g of
11 Instruments and equipment
NOTE. All glassware must be soaked in nitric acid solution (1 + 5) overnight and rinsed with water for later use.
11.1 Spectrophotometer. with 1 cm cuvette.
11.2 Analytical balance. with a division of 0.1 mg.
12 Analysis procedure
12.1 Pretreatment of samples
The same as subclause 5.1.
12.2 Determination
12.2.1 Plotting of standard curves
Respectively PIPETTE 0 mL, 0.250 mL, 0.500 mL, 1.00 mL, 2.00 mL, 3.00 mL, 4.00 mL, 5.00 mL of nickel standard use solution (10.0 mg/L) to 100-mL
volumetric flasks, ADD food simulants to the mark, the corresponding
concentration series are 0 ??g/L, 25.0 ??g/L, 50.0 ??g/L, 100 ??g/L, 200 ??g/L, 300 ??g/L, 400 ??g/L and 500 ??g/L. ADD sodium hydroxide solution (20 %) to adjust to neutral or weak alkaline, LET STAND for 2 h, FILTER, TRANSFER the filtrate into a 250-mL separatory funnel, ADD 2 mL of diammonium hydrogen nitrite solution (100 g/L), ADD a few drops of ammonia solution (2 mol/L) to adjust the solution pH to 8 ~ 9. ADD 2 mL of dimethylglyoxime ethanol solution (10 g/L), ADD 10 mL of chloroform, vigorously SHAKE for 1 min, LET STAND,
SEPARATE chloroform into a 60-mL separatory funnel. ADD 5 mL of chloroform to the aqueous layer and REPEAT the above operations twice, COMBINE
chloroform solution, DISCARD the aqueous layer. USE 10 mL of ammonia
solution (0.3 mol/L) to wash the chloroform layer, vigorously SHAKE for 30 s, LET STAND, SEPARATE the chloroform layer into another 60-mL separatory
funnel; ADD 10 mL of hydrochloric acid solution (0.5 mol/L) to the funnel, vigorously SHAKE for 1 min, LET STAND, SEPARATE the chloroform layer into another separatory funnel. ADD 5 mL of hydrochloric acid solution (0.5 mol/L) and operate as above, COMBINE the hydrochloric acid solution, TRANSFER
to a 25-mL colorimetric tube with stopper, ADD 2 mL of bromine water, SHAKE. LET STAND for 1 min, ADD ammonia solution (5 mol/L) until colorless, ADD 2 mL of ammonia solution (5 mol/L), COOL to room temperature in running water. ADD 2 mL of basic dimethylglyoxime solution (10 g/L), ADD water to 25 mL and MIX thoroughly, LET STAND for 20 min. DETERMINE the absorbance at 540
nm. TAKE the absorbance as the ordinate and the standard concentration as

View full details