GB 1886.336-2021 PDF in English
GB 1886.336-2021 (GB1886.336-2021) PDF English
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GB 1886.336-2021 | English | 125 |
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National food safety standard - Food additives - Sodium dihydrogen phosphate
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Standards related to (historical): GB 1886.336-2021
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GB 1886.336-2021: PDF in English GB 1886.336-2021
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
National food safety standard - Food additives -
Sodium dihydrogen phosphate
ISSUED ON: FEBRUARY 22, 2021
IMPLEMENTED ON: AUGUST 22, 2021
Issued by: National Health Commission of the People's Republic of China;
State Administration for Market Regulation.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Molecular formula and relative molecular mass ... 4
3 Technical requirements ... 4
Annex A Inspection methods ... 6
National food safety standard - Food additives -
Sodium dihydrogen phosphate
1 Scope
This Standard is applicable to the food additive sodium dihydrogen phosphate
produced with sodium hydroxide (or sodium carbonate) and food additive
phosphoric acid (including wet-process phosphoric acid) as raw materials.
2 Molecular formula and relative molecular mass
2.1 Molecular formula
Sodium dihydrogen phosphate anhydrous: NaH2PO4
Sodium dihydrogen phosphate monohydrate: NaH2PO4ꞏH2O
Sodium dihydrogen phosphate dihydrate: NaH2PO4ꞏ2H2O
2.2 Relative molecular mass
Sodium dihydrogen phosphate anhydrous: 119.98 (according to 2018
international relative atomic mass)
Sodium dihydrogen phosphate monohydrate: 137.99 (according to 2018
international relative atomic mass)
Sodium dihydrogen phosphate dihydrate: 156.01 (according to 2018
international relative atomic mass)
3 Technical requirements
3.1 Sensory requirements
The sensory requirements shall meet the requirements of Table 1.
Table 1 -- Sensory requirements
Annex A
Inspection methods
WARNING: Some reagents used in this standard test method are toxic or
corrosive. Appropriate safety and protection determines should be taken
during operation. When necessary, it should be carried out in a fume hood.
If it splashes on the skin, it should be rinsed with water immediately, and
the severe cases should be treated immediately.
A.1 General
The reagents and water used in this Standard refer to analytically-pure reagents
and grade three water specified in GB/T 6682 when other requirements are not
indicated. All standard solutions, preparations and products for the
determination of impurities used in the test, when no other requirements are
specified, are prepared according to GB/T 601, GB/T 602, GB/T 603. The
solution used refers to an aqueous solution when it is not specified which
solvent is used for preparation.
A.2 Identification test
A.2.1 Reagents and materials
A.2.1.1 Ammonia solution: 2+3.
A.2.1.2 Nitric acid solution: 1+8.
A.2.1.3 Silver nitrate solution: 17g/L.
A.2.2 Identification method
A.2.2.1 Identification of phosphate
Weigh 1g of specimen. Dissolve in 20mLof water. Add silver nitrate solution.
Generate yellow precipitate. This precipitate can be dissolved in ammonia
solution or nitric acid solution.
A.2.2.2 Identification of sodium ion
Weigh 1g of specimen. Add 20mLof water to dissolve. Dip a platinum wire ring
in hydrochloric acid. Burn to colorless on the flame. Dip the test solution and
burn on the flame. The flame shall be bright yellow.
A.3 Determination of sodium dihydrogen phosphate (NaH2PO4) (on a dry
basis) content
Where,
5.0 - The volume of hydrochloric acid standard titration solution added, in
milliliters (mL);
c1 - The concentration of hydrochloric acid standard titration solution, in moles
per liter (mol/L);
V - The volume of sodium hydroxide standard titration solution consumed when
titrating to pH≈4.0 when the sudden jump occurs, in milliliters (mL);
c2 - The concentration of sodium hydroxide standard titration solution, in moles
per liter (mol/L).
When V1< 0, the mass fraction w1 of sodium dihydrogen phosphate (NaH2PO4)
is calculated according to formula (A.2).
When V1≥0, the mass fraction w1 of sodium dihydrogen phosphate (NaH2PO4)
is calculated according to formula (A.3).
Where,
V2 - The volume of sodium hydroxide standard titration solution consumed for
titration between pH≈4.0 and pH≈8.8, in milliliters (mL);
c2 - The concentration of sodium hydroxide standard titration solution, in moles
per liter (mol/L);
V1 - The volume of hydrochloric acid standard titration solution consumed when
titrated to pH≈4.0 when a sudden jump occurs, in milliliters (mL);
c1 - The concentration of hydrochloric acid standard titration solution, in moles
per liter (mol/L);
M - The molar mass of sodium dihydrogen phosphate (nah2po4), in grams per
mole (g/mol) (M = 119.98);
10-3 - The conversion factor;
m1 - The specimen mass, in grams (g).
Weigh about 10g of specimen, to the nearest of 0.01g. Place in a 400mL beaker.
Add 100mL of water and heat to boil. While it is hot, use the glass sand crucible
that has been pre-baked at 105°C±2°C electric heating constant temperature
drying oven to constant mass for suction-filtration. Wash the water insoluble
matter with 200mL of hot water 10 times. Put the glass sand crucible together
with the water-insoluble matter in a 105°C±2°C electric heating constant
temperature drying box until the mass is constant.
A.5.3 Result calculation
The mass fraction w3 of water-insoluble matter is calculated according to
formula (A.5).
Where,
m4 - The mass of water insoluble matter and glass sand crucible, in grams (g);
m5 - The mass of glass sand crucible, in grams (g);
m6 - The mass of specimen, in grams (g);
w2 - The mass fraction of loss on drying determined according to A.4, %.
The test results are based on the arithmetic mean of the parallel determination
results. The absolute difference between two independent determination results
obtained under repeatability conditions is not more than 0.01%.
A.6 Determination of pH (10g/L aqueous solution)
A.6.1 Reagents and materials
Carbon dioxide-free water.
A.6.2 Instruments and equipment
Acidity meter: Resolution is 0.01pH; equipped with glass electrode and
saturated calomel electrode (or composite electrode).
A.6.3 Analysis steps
Weigh 1.00g±0.01g of specimen. Place in a 100mL beaker. Use carbon dioxide-
free water to dissolve. Transfer to a 100mL volumetric flask. Use carbon
dioxide-free water to dilute to the scale mark. Shake well. Pour into a 100mL
dry beaker. Use a calibrated acid meter to determine the pH of the test solution.
...... Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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