GB 5009.90-2016 PDF in English
GB 5009.90-2016 (GB5009.90-2016) PDF English
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Name of Chinese Standard | Status |
| GB 5009.90-2016 | English | 70 |
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National Food Safety Standard -- Determination of Iron in Foods
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| GB/T 5009.90-2003 | English | 70 |
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Determination of iron, magnesium and manganese in foods
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Standards related to (historical): GB 5009.90-2016
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GB 5009.90-2016: PDF in English GB 5009.90-2016
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
National food safety standard -
Determination of iron in foods
ISSUED ON. DECEMBER 23, 2016
IMPLEMENTED ON. JUNE 23, 2017
Issued by. National Health and Family Planning Commission of the PRC;
State Food and Drug Administration.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Principles ... 4
3 Reagents and materials ... 4
4 Instrument and equipment ... 5
5 Analytical procedures ... 6
6 Analysis results expression ... 8
7 Precision... 9
8 Others ... 9
Appendix A Microwave digestion temperature-rise program ... 10
Appendix B Reference conditions of flame atomic absorption spectrometry . 11
Foreword
This standard replaces methods for the determination of iron content in GB
5413.21-2010 "National food safety standard - Determination of calcium, iron,
zinc, sodium, potassium, magnesium, copper and manganese in foods for
infants and young child"; GB/T 23375-2009 “Determination of copper, iron, zinc,
calcium, magnesium and phosphorus content in vegetables and derived
products”; GB/T 5009.90-2003 “Determination of iron, magnesium and
manganese in foods”; GB/T 14609-2008 “Inspection of grain and oils -
Determination of copper, iron, manganese, zinc, calcium, magnesium in cereals
and derived products by atomic absorption and flame spectrophotometry”;
GB/T 18932.12-2002 “Method for the determination of potassium, sodium,
calcium, magnesium, zinc, iron, copper, manganese, chromium, lead, cadmium
contents in honey - Atomic absorption spectrometry”; GB/T 9695.3-2009 “Meat
and meat products - Determination of iron content”; NY/T 1201-2006
“Determination of copper, iron and zinc content in vegetables and derived
products”.
As compared with GB/T 5009.90-2003, the main changes of this standard are
as follows.
--- Standard name is changed to "National food safety standard -
Determination of iron in foods";
--- Add microwave digestion, pressure tank digestion and dry digestion;
--- Add the inductively coupled plasma emission spectrometry;
--- Add the inductively coupled plasma mass spectrometry;
--- Delete spectrophotometry.
National Food Safety Standard -
Determination of iron in foods
1 Scope
This standard specifies the determination of iron content in foods by flame
atomic absorption spectrometry, inductively coupled plasma emission
spectrometry and inductively coupled plasma mass spectrometry.
This standard applies to the determination of iron content in foods.
Method I. Flame atomic absorption spectrometry
2 Principles
After digestion, the sample is atomized by atomic absorption and the
absorbance value is measured at 248.3 nm. Within a certain concentration
range, iron absorbance value is directly proportional to iron content; compares
with the standard series for quantitation.
3 Reagents and materials
Unless otherwise indicated, the reagents used in this method are guaranteed
reagent, the water is the grade-2 water specified in GB/T 6682.
3.1 Reagents
3.1.1 Nitric acid (HNO3).
3.1.2 Perchloric acid (HClO4).
3.1.3 Sulfuric acid (H2SO4).
3.2 Reagent preparation
3.2.1 Nitric acid solution (5+95). MEASURE 50 mL of nitric acid; POUR into
950mL of water; MIX it uniformly.
3.2.2 Nitric acid solution (1+1). MEASURE 250 mL of nitric acid; POUR into 250
mL of water; MIX it uniformly.
5.2.2 Microwave digestion
Accurately WEIGH 0.2 g ~ 0.8 g of solid sample (accurate to 0.001 g) or
accurately MOVE 1.00 mL ~ 3.00 mL of liquid sample into microwave digestion
tank; ADD 5mL of nitric acid; DIGEST the sample according to the microwave
digestion steps, digestion conditions refer to Table A.1; TAKE out the digestion
tank after cooling; CATCH-acid to about 1.0 mL on a hot plate at 140°C ~ 160°C.
After cooling, TRANSFER the digestion juice into a 25 mL volumetric flask; USE
a small amount of water to wash the inner tank and the inner caps for 2~3 times;
COMBINE washing liquid in the volumetric flask; Use water to dilute it to the
mark; MIX it uniformly for spare-use. Meanwhile, DO a sample blank test.
5.2.3 Pressure-tank digestion
Accurately WEIGH 0.3 g ~ 2 g of solid sample (accurate to 0.001 g) or
accurately MOVE 2.00 mL ~ 5.00 mL of liquid sample into digestion inner-tank;
ADD 5 mL of nitric acid; COVER inner-cap; TIGHTEN stainless steel outer-
sheath; PLACE it into constant temperature oven at 140°C ~ 160°C for 4h ~ 5h.
Slowly LOOSEN the outer tank after cooling; TAKE it out and DIGEST the inner
tank; CATCH-acid to about 1.0 mL on adjustable electric hot plate at 140°C ~
160°C. After cooling, TRANSFER the digestion juice into a 25mL volumetric
flask; USE a small amount of water to wash the inner tank and the inner caps
for 2~3 times; COMBINE washing liquid in the volumetric flask; Use water to
dilute it to the mark; MIX it uniformly for spare-use. Meanwhile do a sample
blank test.
5.2.4 Dry digestion
Accurately WEIGH 0.5 g ~ 3 g of solid sample (accurate to 0.001 g) or
accurately MOVE 2.00 mL ~ 5.00 mL of liquid sample into a crucible; HEAT it in
soft fire; CARBONIZE to smokeless; TRANSFER it into a muffle furnace; ASH
at 550°C for 3h ~ 4h. Take out after cooling; for sample that is not completely
ashed, ADD a few drops of nitric acid; HEAT in soft fire; EVAPORATE carefully;
TRANSFER it into a muffle furnace at 550°C; CONTINUE ashing for 1h ~ 2h
until the sample is in white-gray; TAKE out after cooling; DISSOLVE it with
appropriate amount of nitric acid solution (1+1); TRANSFER it into a 25 mL
volumetric flask. USE a small amount of water to wash the inner tank and the
inner caps for 2~3 times; COMBINE washing liquid in the volumetric flask; Use
water to dilute it to the mark. Meanwhile. DO a sample blank test.
5.3 Determination
5.3.1 Instrument’s test conditions
Reference conditions are shown in Table B.1.
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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