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GB 1886.374-2024 English PDF

GB 1886.374-2024 English PDF

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GB 1886.374-2024: National Food Safety Standards--Food Additives--Cellulose
GB 1886.374-2024
GB
NATIONAL STANDARD OF THE
PEOPLE?€?S REPUBLIC OF CHINA
National food safety standard - Food additive - Cellulose
ISSUED ON: FEBRUARY 08, 2024
IMPLEMENTED ON: AUGUST 08, 2024
Issued by: National Health and Health Commission of PRC;
State Administration for Market Regulation.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Chemical name, molecular formula, structural formula, relative molecular mass ... 4
3 Technical requirements ... 4
Appendix A Test method ... 6
Appendix B Standard reference infrared spectrum of cellulose ... 12
Appendix C Conversion of relative viscosity (??rel) and the product of intrinsic viscosity
and concentration [??]C ... 13
National food safety standard - Food additive - Cellulose
1 Scope
This standard applies to food additive cellulose, which is obtained by purifying and
mechanically crushing fibrous plant pulp containing ??-cellulose as raw material.
2 Chemical name, molecular formula, structural formula,
relative molecular mass
2.1 Chemical name
Cellulose
2.2 Molecular formula
(C6H10O5)n
2.3 Structural formula
2.4 Relative molecular mass
(162.14)n (according to the 2018 international relative atomic mass)
3 Technical requirements
3.1 Sensory requirements
Sensory requirements shall comply with the provisions of Table 1.
Appendix A
Test method
A.1 Safety tips
Some reagents used in the test method of this standard are toxic or corrosive.
Appropriate safety and health measures shall be taken during operation. If splashed on
the skin, rinse with water immediately. In severe cases, treatment shall be given
immediately. When using flammable materials, it is strictly forbidden to use open
flames for heating.
A.2 General provisions
The reagents and water used in this standard refer to analytical pure reagents and grade
3 water specified in GB/T 6682, unless otherwise specified. The standard titration
solution, standard solution for impurity determination, preparations and products used
in the test shall be prepared, in accordance with the provisions of GB/T 601, GB/T 602,
GB/T 603, unless otherwise specified. The solutions used in the test refer to aqueous
solutions unless otherwise specified.
A.3 Identification test
A.3.1 Solubility test
Insoluble in water, ethanol, ether, diluted inorganic acid. Slightly soluble in 1 mol/L
sodium hydroxide solution.
A.3.2 Suspension test
Mix 30 g of specimen with 270 mL of water. Stir the mixture with a high-speed stirrer
(about 12000 r/min) for 5 min. The final solution is a suspension with poor fluidity,
thick, lumpy matter. If a free-flowing suspension is obtained, take 100 mL of the
solution; place it in a 100 mL measuring cylinder; let it stand for 1 h; then a precipitate
will appear at the bottom of the measuring cylinder.
A.3.3 Infrared spectrum identification
The test is carried out according to GB/T 6040 using the potassium bromide tablet
method. The infrared spectrum of the specimen shall be consistent with the standard
reference spectrum of cellulose (see Appendix B).
A.3.4 Polymerization test
A.3.4.1 Reagents and materials
Ethylenediamine copper dihydroxide solution: 1.0 mol/L.
A.3.4.2 Instruments and equipment
A.3.4.2.1 Balance: Sensitivity is 0.1 mg.
A.3.4.2.2 Constant temperature water bath (tank).
A.3.4.2.3 Ubbelohde viscometer: Capillary inner diameters are 0.5 mm ~ 0.6 mm and
0.7 mm ~ 0.8 mm, respectively.
A.3.4.3 Analytical procedures
Weigh about 0.25 g (m1) of specimen. Place it in a stoppered conical flask. Add 25 mL
of water and 25 mL of 1.0 mol/L copper dihydroxide solution, respectively. Add the
stopper and shake to completely dissolve. Transfer an appropriate amount of the
solution to an Ubbelohde viscometer (capillary inner diameter 0.7 mm ~ 0.8 mm; select
an appropriate viscometer constant K1). Balance it in a 25 ??C ?? 0.1 ??C water bath for at
least 5 min. Record the time the solution flows through the upper and lower scales of
the Ubbelohde viscometer (do not reload the specimen; repeat the measurement twice;
the difference in the flow time of the two measurements shall not exceed ??0.5% of the
average value). Take the average of the two measurements as the outflow time t1 of the
solution. Calculate the kinematic viscosity ??1 of the solution according to formula (A.1):
Where:
t1 - The time the solution flows through the upper and lower scales of the Ubbelohde
viscometer, in seconds (s);
K1 - Viscometer constant.
Take an appropriate amount of 0.1 mol/L copper dihydroxide ethylenediamine solution.
Mix it with an equal amount of water. Use an Ubbelohde viscometer (capillary inner
diameter 0.5 ~ 0.6 mm; select an appropriate viscometer constant K2), to determine the
outflow time t2 in the same way. The kinematic viscosity ??2 of the blank solution is
calculated according to formula (A.2):
Where:
t2 - The time for the solution to flow through the upper and lower scales of the
Ubbelohde viscometer, in seconds (s);
K2 - Viscometer constant.
Calculate the relative viscosity ??rel according to formula (A.3):
Weigh about 125 mg of specimen (m2), accurate to 0.1 mg. Use about 25 mL of water,
to transfer it into a 300 mL conical flask. Add 50.0 mL of potassium dichromate solution
(A.4.2.2). Mix well. Then slowly add 100 mL of sulfuric acid (A.4.2.1). Heat to boiling.
Remove the heat source. Let it stand at room temperature for 15 minutes. Cool it in
water bath. Transfer it into a 250 mL volumetric flask. Use water to dilute it to close to
the mark. Cool to room temperature. Use water to dilute it to the mark. Mix well.
Measure 50.0 mL of the solution. Add 2 ~ 3 drops of 1,10-phenanthroline-ferrous
indicator solution (A.4.2.4). Use 0.1 mol/L ammonium ferrous sulfate standard titration
solution (A.4.2.3) to titrate it, until the reddish brown color appears, which is taken as
the end point. Record the consumed volume. At the same time, perform a blank test.
Record the consumed volume of 0.1 mol/L ammonium ferrous sulfate standard titration
solution (A.4.2.3).
A.4.5 Calculation of results
The mass fraction w2 of cellulose content (measured in C6H10O5, on a dry basis) is
calculated according to formula (A.5):
Wherein:
c - Concentration of standard ammonium ferrous sulfate titration solution, in mol/L;
V3 - Volume of standard ammonium ferrous sulfate titration solution consumed in
the blank test, in milliliters (mL);
V4 - Volume of standard ammonium ferrous sulfate titration solution consumed by
the specimen, in milliliters (mL);
m2 - Mass of the specimen, in milligrams (mg);
w1 - Loss on drying of the specimen, %;
6.75 - Number of milligrams of C6H10O5 equivalent to each millimole of standard
ammonium ferrous sulfate titration solution {c[(NH4)2Fe(SO4)2]};
50 - Volume of specimen solution pipetted, in milliliters (mL);
250 - Volume of specimen solution fixed, in milliliters (mL).
The test result shall be based on the arithmetic mean of the results of parallel
determinations. The absolute difference between two independent determination results,
as obtained under repeatability conditions, shall not be greater than 1% of the arithmetic
mean.
A.5 Determination of pH (10% solution)
Weigh 10.0 g of the specimen, which is dried at 105 ??C ?? 2 ??C for 3 hours. Mix with
90 mL of water. Let stand for 1 hour. Stir from time to time. Centrifuge it. Then use a
pH meter to determine the pH of the supernatant, according to the method specified in
GB/T 9724.
A.6 Determination of water-soluble substances
A.6.1 Reagents and materials
Medium-speed qualitative filter paper.
A.6.2 Instruments and equipment
A.6.2.1 Balance: Sensitivity 0.1 mg.
A.6.2.2 Electric constant temperature drying oven: Temperature control range 105 ??C
?? 2 ??C.
A.6.2.3 Constant temperature water bath.
A.6.3 Analytical procedures
Weigh about 6 g of the specimen (m3) dried at 105 ??C ?? 2 ??C for 3 h, accurate to 0.1
mg. Mix with 90 mL of water which is freshly boiled and cooled to room temperature.
Let stand for 10 min. Stir from time to time. Filter it. Discard 10 mL of the initial filtrate.
If necessary, re-filter the remaining filtrate to obtain a clear filtrate. Take 15 mL of the
filtrate. Transfer it to an evaporating dish of known mass (m5). Place it on a steam bath
and evaporate to dryness. Then dry at 105 ??C for 1 h. Cool in a desiccator and weigh it
(m4).
A.6.4 Result calculation
The mass fraction of water-soluble matter w3 is calculated according to formula (A.6):
Where:
m4 - The total mass of the evaporating dish and the dried matter after drying, in
grams (g);
m5 - The mass of the evaporating dish, in grams (g);
m3 - The mass of the specimen, in grams (g);

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