Powered by Google www.ChineseStandard.net Database: 189760 (20 Apr 2024)

GB 1886.4-2020 (GB1886.4-2020)

Standard IDContents [version]USDSTEP2[PDF] delivered inName of Chinese StandardStatus
GB 1886.4-2020English140 Add to Cart 0-9 seconds. Auto-delivery. National food safety standard - Food additive - Sodium hexametaphosphate Valid


Standards related to: GB 1886.4-2020

GB 1886.4-2020: PDF in English

GB 1886.4-2020
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
National Food Safety Standard -
Food Additive - Sodium Hexametaphosphate
ISSUED ON: SEPTEMBER 11, 2020
IMPLEMENTED ON: MARCH 11, 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 Technical Requirements ... 4 
Appendix A Inspection Methods ... 6 
National Food Safety Standard - Food Additive -
Sodium Hexametaphosphate
1 Scope
This Standard is applicable to food additive sodium hexametaphosphate, which is
generated by the melt polymerization reaction of sodium carbonate or sodium
hydroxide and food additive phosphoric acid (including phosphoric acid by wet
process).
2 Technical Requirements
2.1 Sensory Requirements
Sensory requirements shall comply with the stipulations of Table 1.
Table 1 -- Sensory Requirements
Item Requirements Inspection Methods
Color Colorless and transparent, or white Take an appropriate amount of specimen; place
it in a 50 mL beaker; under natural light, observe
its color and state
State Glassy flake, granule or powder
2.2 Physical and Chemical Indicators
The physical and chemical indicators shall comply with the stipulations of Table 2.
Appendix A
Inspection Methods
A.1 Warning
Some reagents used in the inspection methods of this Standard are toxic or corrosive,
so be careful when handling them! If they splash on the skin or eyes, immediately use
plenty of water for rinsing. In severe cases, medical treatment shall be immediately
sought. For the flammable products used in the tests, no open flame shall be used
during operation.
A.2 General Rules
Unless other requirements are indicated, the reagents and water used in this Standard
refer to analytically pure reagents and Grade-3 water specified in GB/T 6682. Unless
other requirements are indicated, the standard titration solutions, preparations and
products used in the tests are all prepared in accordance with GB/T 601, GB/T 602
and GB/T 603. When it is not specified which solvent is used for preparation, the used
solution refers to an aqueous solution.
A.3 Identification and Test
A.3.1 Reagents and materials
A.3.1.1 Hydrochloric acid.
A.3.1.2 Nitric acid solution: 1 + 7.
A.3.1.3 Silver nitrate solution: 17 g/L.
A.3.1.4 Sodium hydroxide solution: 40 g/L.
A.3.1.5 Platinum-wire ring.
A.3.2 Identification methods
A.3.2.1 Sodium ion
After using hydrochloric acid to wet the platinum-wire ring, burn it on colorless flame,
until it becomes colorless. Dip the specimen; burn it in colorless flame; the flame shall
be luminous yellow.
A.3.2.2 Phosphate
Weigh-take 0.1 g of specimen; place it in a 50 mL beaker. Add 5 mL of hot nitric acid
A.5.3.1 Sintered-glass filter crucible: the aperture of the filter plate is 5 μm ~ 15 μm.
A.5.3.2 Electrothermal constant-temperature drying oven: the temperature is
controlled at 180 °C ± 5 °C or 250 °C ± 10 °C.
A.5.4 Analytical procedures
Use a pipette to transfer-take 50 mL of the specimen solution (see A.4.4.1); place it in
a 100 mL volumetric flask. While constantly shaking it, add 30 mL of barium chloride
solution; thoroughly shake it to complete the precipitation. Then, use water to dilute to
the scale; shake it well; dry-filter it. Use a pipette to transfer-take 50 mL of filtrate; place
it in a 400 mL tall beaker. Add 15 mL of nitric acid solution and 35 mL of water; heat it
up and boil it for 15 min. While it is still hot, add 20 mL of quin-molybdenum-ketone
solution; use a watch glass to cover it; preserve the heat for 10 min (in the process of
adding reagents and heating, DO NOT use open flame, DO NOT stir it, so as avoid
condensation into lumps), then, cool it down to room temperature. Use a sintered-glass
filter crucible, which is dried to a constant mass at 180 °C ± 5 °C or 250 °C ± 10 °C, to
filter it by the pouring method. In a beaker, rinse and precipitate it for 3 times, with 15
mL of water each time. Transfer all the precipitate to the sintered-glass filter crucible,
then, continue to use water to rinse it (the used rinsing water is about 150 mL). At
180 °C ± 5 °C, dry it for 45 min, or at 250 °C ± 10 °C, dry it for 30 min. In a desiccator,
cool it down; weigh it.
A.5.5 Result calculation
The mass fraction w2 of inactive phosphate (calculated as P2O5) shall be calculated in
accordance with Formula (A.2):
Where,
m3---the mass of quinoline phosphomolybdate precipitate, expressed in (g);
0.03207---conversion factor of quinoline phosphomolybdate and phosphorus
pentoxide;
20---dilution factor;
m2---the mass of specimen (see A.4.4.1), expressed in (g).
The test results shall be subject to the arithmetic mean value of the parallel
determination results. The absolute difference between two independent determination
results obtained under repeatability conditions is not greater than 0.3%.
A.6 pH (10 g/L solution) Determination
The test results shall be subject to the arithmetic mean value of the parallel
determination results. The absolute difference between two independent determination
results obtained under repeatability conditions is not greater than 0.1%.
A.8 Determination of Iron (Fe)
A.8.1 Method summary
Use ascorbic acid to reduce the trivalent iron ions in the specimen solution to divalent
iron ions. When the pH is 2 ~ 9, the divalent iron ions and o-phenanthroline generate
orange-red complexes. Use a spectrophotometer to determine its absorbance at the
wavelength of 510 nm.
A.8.2 Reagents and materials
Same as Chapter 4 of GB/T 3049-2006.
A.8.3 Instruments and equipment
Same as Chapter 5 of GB/T 3049-2006.
A.8.4 Analytical procedures
A.8.4.1 Drawing of standard curve
In accordance with the stipulations of 6.3 in GB/T 3049-2006, in six 100 mL volumetric
flasks, prepare series standard solutions with the mass (mg) of iron (Fe) per 100 mL:
0.00 mg, 0.01 mg, 0.02 mg, 0.04 mg, 0.08 mg and 0.10 mg. Use 4 cm or 5 cm cuvette
to determine the absorbance of the standard solutions. Take the mass (mg) of iron (Fe)
per 100 mL as the x-coordinate; take the corresponding absorbance as the y-
coordinate; draw a standard curve.
A.8.4.2 Determination
Weigh-take about 3 g of specimen, accurate to 0.0002 g; place it in a 250 mL beaker.
Add 50 mL of water and 10 mL of hydrochloric acid solution; use a watch glass to cover
it. Heat it up and boil it for 15 min, then, cool it down to room temperature. Transfer all
to a 250 mL volumetric flask; use water to dilute to the scale; shake it well. Use a
pipette to transfer-take 25 mL of the test solution; place it in a 100 mL volumetric flask.
The subsequent steps shall follow the operations in 6.4 of GB/T 3049-2006, starting
from “if necessary, add water to 60 mL……”.
At the same time, conduct a blank test. Except that no specimen is added, the blank
test solution is the same as the test solution in the other operations and the added
reagents.
In accordance with the measured absorbance, from the standard curve, find out the
electrode as the measuring electrode; use the standard curve method to determine the
fluoride content.
A.12.2 Reagents and materials
A.12.2.1 Hydrochloric acid solution: 1 + 4.
A.12.2.2 Total ionic strength adjustment buffer (TISAB): in accordance with the
requirements of HG/T 3696.3, prepare it right before use.
A.12.2.3 Fluoride (F) standard solution: 1 mL contains 0.01 mg of fluoride (F). Use a
pipette to transfer-take 10 mL of fluoride (F) standard solution, which is prepared in
accordance with GB/T 602; place it in a 100 mL volumetric flask; use water to dilute to
the scale; shake it well.
A.12.3 Instruments and equipment
A.12.3.1 pH meter: with a division value of 1 mV; equipped with saturated calomel
electrode and fluoride ion selective electrode.
A.12.3.2 Magnetic stirrer.
A.12.4 Analytical procedures
A.12.4.1 Drawing of standard curve
In five 50 mL volumetric flasks, use a pipette to respectively add 1.00 mL, 2.00 mL,
3.00 mL, 4.00 mL and 5.00 mL of the fluoride (F) standard solution; accurately add 4
mL of hydrochloric acid solution; add 25 mL of the total ionic strength adjustment buffer
(TISAB); use water to dilute to the scale; shake it well. Connect the fluoride ion
selective electrode and the saturated calomel electrode to the negative and positive
ends of the pH meter. Insert the electrode into a 50 mL polyethylene beaker, which is
filled with water. Under electromagnetic stirring, read the equilibrium potential value,
replace the water, in which, the electrode is immersed, then, after the potential value
reaches an equilibrium, from low to high concentration, respectively determine the
potential value of the fluorine standard solution. Take the potential value as the y-
coordinate; take the logarithm of the fluoride mass (mg) as the x-coordinate; draw a
standard curve.
A.12.4.2 Determination
Weigh-take about 1 g of specimen, accurate to 0.0002 g; place it in a 50 mL
polyethylene beaker. Add a small amount of water to moisten it; accurately add 4 mL
of hydrochloric acid solution to dissolve it. Then, transfer all to a 50 mL volumetric flask.
Add 25 mL of the total ionic strength adjustment buffer (TISAB); use water to dilute to
the scale; shake it well. Determine the potential value of the test solution. In
accordance with the determined potential value, from the standard curve, find out the
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.