Powered by Google www.ChineseStandard.net Database: 189760 (25 May 2024)

GB/T 5009.81-2003 PDF in English


GB/T 5009.81-2003 (GB/T5009.81-2003, GBT 5009.81-2003, GBT5009.81-2003)
Standard IDContents [version]USDSTEP2[PDF] delivered inName of Chinese StandardStatus
GB/T 5009.81-2003English70 Add to Cart 0-9 seconds. Auto-delivery. Method for analysis of hygienic standard of stainless-steel food containers and table wares Valid


Standards related to: GB/T 5009.81-2003

GB/T 5009.81-2003: PDF in English (GBT 5009.81-2003)

GB/T 5009.81-2003
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 67.040
C 53
Replacing GB/T 11681-1989
Method for Analysis of Hygienic Standard of Stainless
Steel Food Containers and Table Wares
ISSUED ON. AUGUST 11, 2003
IMPLEMENTED ON. JANUARY 01, 2004
Issued by. Ministry of Health of the People's Republic of China;
Standardization Administration of the People's Republic of
China.
Table of Contents
1  Scope ... 4 
2  Normative References ... 4 
3  Preparation of Samples ... 4 
4  Determination of Chromium, Lead and Nickel ... 5 
5  Determination of Cadmium ... 12 
6  Determination of Arsenic ... 12 
Foreword
This Standard replaces GB/T 11681-1989 “Method for Analysis of Hygienic Standard of
Stainless Steel Food containers and Table Wares”.
Compared with GB/T 11681-1989, the major changes of this Standard are as follows.
- According to GB/T 20001.4-2001 “Rules for Drafting Standards - Part 4. Methods for
Chemical Analysis”, the structure of the previous standard is changed.
This Standard was proposed by and shall be under the jurisdiction of the Ministry of Health
of the People's Republic of China.
This Standard was responsibly drafted by Shangxi Province Health and Anti-Epidemic
Station, and Liaoning Province Food Hygiene Supervision and Inspection Institute.
The main drafters of this Standard. Li Wenyuan, Liu Guoxiang, Shi Chongyi, Lu Guihua,
Xu Min, Li Min and Zhang Hua.
The previous standard was first-time released in 1989; and this is the first revision.
Method for Analysis of Hygienic Standard of Stainless
Steel Food Containers and Table Wares
1 Scope
This Standard specifies the method for the analysis of the hygienic standard of stainless
steel food containers and table wares.
This Standard applies to the determination of all hygienic indicators of all kinds of kitchen
wares, table wares, food containers, as well as other containers, wares and devices in
contact with foods, which are made of the material of stainless steel.
2 Normative References
The provisions in the following documents become the provisions of this Standard through
the reference of this Standard. For the dated reference documents, none of their
subsequent amendments (excluding corrigendum) or revisions apply to this Standard.
However, all parties who reach an agreement according to this Standard are encouraged
to study whether the latest editions of these documents can be applied. For the undated
reference documents, their latest editions apply to this Standard.
GB/T 5009.12 Determination of Lead in Foods
GB/T 5009.62 Method for Analysis of Hygienic Standard of Ceramics for Food
Containers
GB/T 5009.72 Method for Analysis of Hygienic Standard of Aluminum-Wares for Food
Use
3 Preparation of Samples
3.1 Sampling Method
Take samples according to 0.1% of the product quantity; produce in small batches; take at
least 6 samples each time; indicate respectively the product name, batch number, steel
number and sampling date. One half of the samples are used for laboratory test and the
other half are stored for two months to be used for arbitration analysis.
3.2 Visual inspection
generated during atomization absorbs certain radiation energy; the absorption amount is
proportional to the content of the metallic elements; then the content of the samples can
be quantified by comparing with the standard series.
4.1.2 Reagents
4.1.2.1 50 g/L ammonium dihydrogen phosphate solution. weigh 5 g of ammonium
dihydrogen phosphate (NH4H2PO4, guaranteed reagent); add water to dissolve and dilute
to 100 mL.
4.1.2.2 Chromium standard solution. weigh precisely 2.828 9 g of potassium dichromate
(K2Cr2O7, reference reagent); dry to constant volume at 105 °C ~ 110 °C; add 50 mL of
water to dissolve before transferring to a 1 000 mL volumetric flask; add 2 mL of nitric acid;
shake and add water to dilute to the scale mark. The solution contains 1 mg of chromium
per milliliter.
4.1.2.3 Lead standard solution. weigh precisely 1.000 0 g of metal lead (Pb, 99.99%); add
5 mL of c(HNO3) = 6 mol/L nitrate to dissolve; transfer to a 1 000 mL volumetric flask; add
water to dilute to the scale mark. This solution contains 1 mg of lead per milliliter.
4.1.2.4 Nickel standard solution. weigh precisely 1.000 0 g of nickel (Ni, 99.99%); add 5
mL of c(HNO3) = 6 mol/L nitric acid to dissolve; transfer to a 1 000 mL volumetric flask; add
water to dilute to the mark. This solution contains 1 mg of nickel per milliliter.
4.1.2.5 Standard solutions of chromium, nickel and lead. before use, dilute gradually the
standard solutions of chromium, nickel and lead, respectively, to the metal standard
working solutions equivalent to 1 μg per milliliter.
4.1.3 Instruments
4.1.3.1 Graphite furnace atomic absorption spectrophotometer.
4.1.3.2 Pyrolytic graphite tube and high purity argon.
4.1.3.3 Trace pipettor.
4.1.4 Analysis steps
4.1.4.1 Preparation of samples and mixed standard series
Draw 0.50 mL ~ 1.00 mL of sample soaking solution to place into a 10 mL volumetric flask;
take another six 10 mL volumetric flasks; draw metal standard working solutions
respectively. chromium. 0, 0.20, 0.40, 0.60, 0.80 and 1.00 mL, nickel. 0, 0.50, 1.00, 1.50,
2.00 and 2.50 mL; lead. 0, 0.30, 0.60, 0.90, 1.20 and 1.50 mL. Add 1.0 mL of 50 g/L
ammonium dihydrogen phosphate solution to the samples and standard tubes; use water
to dilute to the scale mark and mix evenly. The metal contents of the standard series
prepared are - chromium. 0, 0.20, 0.40, 0.60, 0.80, 1.00 μg; nickel. 0, 0.50, 1.00, 1.50, 2.00
S -- area of sample in contact with soaking solution, in square centimeter (cm2);
2 -- 2 mL of soaking solution per square centimeter, in milliliter per square centimeter
(mL/cm2).
4.2 Diphenylcarbazide colorimetry (determination of chromium)
4.2.1 Principle
Use potassium permanganate oxidate low-valent chromium to high-valent chromium (Cr6+);
add sodium pyrophosphate to hide the residual iron; use diphenylcarbazide to produce red
complex with chromium; then quantify by comparing with the standard series.
4.2.2 Reagents
4.2.2.1 Sulfuric acid. c (H2SO4) = 2.5 mol/L. Take 70 mL of guaranteed reagent sulfuric
acid to add to water while stirring; add water to 500 mL after placing aside for cooling.
4.2.2.2 3 g/L potassium permanganate solution. weigh 0.3 g of potassium permanganate
and add water to dissolve to 100 mL.
4.2.2.3 200 g/L urea solution. weigh 20 g of urea and add water to dissolve to 100 mL.
4.2.2.4 100 g/L sodium nitrite solution. weigh 10 g of sodium nitrite and add water to
dissolve to 100 mL.
4.2.2.5 Saturated sodium hydroxide solution.
4.2.2.6 50 g/L sodium pyrophosphate solution. weigh 5 g of sodium pyrophosphate (Na4P
2O7 • 10H2O) and add water to dissolve to 100 mL.
4.2.2.7 Diphenylcarbazide solution. weigh 0.5 g of diphenylcarbazide to dissolve in 50 mL
of acetone; add 50 mL of water; prepare immediately prior to use; store in a brown bottle.
If the color of the solution becomes dark, it shall not be used.
4.2.2.8 Chromium standard solution. the preparation method is the same as 4.1.2.2; the
concentration of the working solution is 10 μg of chromium per milliliter.
4.2.3 Instruments
4.2.3.1 Spectrophotometer and 3 cm cuvettes.
4.2.3.2 25 mL stoppered cuvettes.
4.2.4 Analysis steps
4.2.4.1 Draw standard curves
Draw 0, 0.25, 0.50, 1.00, 1.50, 2.00, 2.50 and 3.00mL of chromium standard working
4.3.2.1 100 g/L ammonium citrate dibasic solution. weigh 10 g of ammonium citrate dibasic
[(NH4)2HC6H5O7] to dissolve in water to 100 mL.
4.3.2.2 10 g/L dimethylglyoxime-ethanol solution. weigh 1 g of dimethylglyoxime [(CH3)2C2
(NOH) 2] to dissolve in ethanol [95% (volume fraction)] to 100 mL; filter if any insoluble
matter; prepare the filtrate for use.
4.3.2.3 10 g/L alkaline dimethylglyoxime solution. weigh 1 g of dimethylglyoxime to dissolve
in c (NaOH) = 0.2 mol/L sodium hydroxide solution to 100 mL.
4.3.2.4 Hydrochloric acid. c (HCI) = 0.5 mol/L.
4.3.2.5 4% (volume fraction) acetic acid.
4.3.2.6 Ammonia. c (NH4OH) = 5 mol/L.
4.3.2.7 Ammonia. c (NH4OH) = 2 mol/L.
4.3.2.8 Ammonia. c (NH4OH) = 0.3 mol/L.
4.3.2.9 20% (volume fraction) sodium hydroxide solution.
4.3.2.10 Nickel standard solution. the preparation method is the same as 4.1.2.4; the
concentration of the working solution is equivalent to 10 μg of nickel per milliliter.
4.3.3 Instruments
4.3.3.1 Spectrophotometer and 1 cm cuvettes.
4.3.3.2 25 mL stoppered cuvettes.
4.3.3.3 125 mL and 60 mL separating funnels.
4.3.4 Analysis steps
4.3.4.1 Draw standard curves
Draw 0, 0.25, 0.50, 1.00, 2.00, 3.00, 4.00 and 5.00 mL of nickel standard working solution;
add 4% acetic acid to 100 mL; transfer to 125 mL separating funnels; operate hereunder
same as the operation of the samples; draw standard curves by taking the absorbance as
ordinate and the standard concentration as abscissa.
4.3.4.2 Determination
Take 100 mL of sample soaking solution; add 20% sodium hydroxide solution to adjust to
neutral or weak alkalinity; place aside for 2 h; filter then transfer the filtrate to a 125 mL
separating funnel; add 2 mL of ammonium citrate dibasic; add several drops of 2 mol/L
ammonia to adjust the pH value of the solution to 8~9. Add 2 mL of dimethylglyoxime
ethanol solution; add 10 mL of chloroform; shake vigorously for 1 min; stand then separate
......
 
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.