Some standard content:
Record number: 3718--1999
HG2928--1999
This standard is a non-equivalent revision of HG2928-1989 "Food Additive Disodium Dihydrogen Pyrophosphate" by adopting the Chemical Industry Standard of the Fourth Edition of the Food Chemical Pharmacopoeia of the United States (1996) [FCCIV (1996)]. The main technical differences between this standard and the Food Chemical Pharmacopoeia of the United States are: pH value is added to the index items, and the lead index is not set. The determination of arsenic content adopts GB/T8450 "Determination of Arsenic in Food Additives". The determination of heavy metals adopts GB/T8451 "Limit Test Method for Heavy Metals in Food Additives". The determination of fluoride adopts the distillation method.
The determination of pH adopts the instrumental method.
The main technical differences between this standard and HG2928--1989 are: The heavy metal index is changed from 0.002% to 0.0015%. The determination of heavy metal content has been improved.
-The packaging capacity has been increased (changed to 25kg packaging), and the shelf life of the product has been increased. Appendix A of this standard is the appendix of the standard. This standard will replace HG2928--1989 from the date of implementation. This standard was proposed by the Technical Supervision Department of the former Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the inorganic salt product standardization technical unit of the Ministry of Chemical Industry and the Food Hygiene Supervision and Inspection Institute of the Ministry of Health. The drafting units of this standard: Tianjin Chemical Research Institute of the Ministry of Chemical Industry and Lianyungang Hongqi Chemical Plant. The main drafters of this standard: Pan Hangjun, Li Guangming, Lu Siwei, Liu Zhen. This standard was first issued as a national standard in March 1989, and was adjusted to a mandatory chemical industry standard in 1997 and renumbered.
This standard is entrusted to the inorganic salt product standardization technical unit of the Ministry of Chemical Industry for interpretation. 810
Chemical Industry Standard of the People's Republic of China
Food additives
Disodium dihydrogen pyrophosphate
Food additive-
Disodium dihydrogen pyrophosphateHG 2928—1999
Replaces HG 2928-1989
This standard specifies the requirements, test methods, inspection rules, and marking, packaging, transportation, and storage of the food additive disodium dihydrogen pyrophosphate.
This standard applies to disodium dihydrogen pyrophosphate made from phosphoric acid and soda ash or sodium dihydrogen phosphate without arsenic. The product is used as a rapid fermentation agent and quality improver in food processing. Molecular formula: NazH, P, O,
Relative molecular mass: 221.94 (according to the international relative atomic mass in 1995) 2 Reference standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB191—1990 Pictorial marking for packaging, storage and transportation
GB/T 601--1988
GB/T 602—1988
GB/T 603--1988
Preparation of standard solutions for titration analysis (volume analysis)Chemical reagents
Chemical reagents
Preparation of standard solutions for impurity determination (negISO6353-1:1982)Chemical reagents
Preparation of preparations and products used in test methods (neqISO6353-1:1982)GB/T6678-1986
General rules for sampling of chemical products
GB/T6682-1992
Specifications and test methods for water used in analytical laboratories (eqvISO3696:1987)GB/T 8450-1987
GB/T 8451-—1987
3 Requirements
Determination of arsenic in food additives
Test method for heavy metal limits in food additives3.1
Appearance: This product is white powder.
3.2 Food additives
Disodium dihydrogen pyrophosphate shall meet the requirements of Table 1. Table 1 Requirements
Content of disodium dihydrogen pyrophosphate (as Na,H,P,0O)/%Content of water-insoluble matter/%
Content of arsenic (As)/%
Approved by the State Administration of Petroleum and Chemical Industry on June 16, 1999
Implementation on June 1, 2000
Content of heavy metals (as Pb)/%
Content of fluoride (as F)/%
pH value (10 g/L solution)
Test method
HG2928—1999
Table 1 (End)
The reagents and water used in this standard, unless otherwise specified, refer to analytically pure reagents and grade 3 water specified in GB/T6682. The standard titration solution, impurity standard solution, preparation and products used in the test shall be prepared in accordance with the provisions of GB/T601, GB/T602 and GB/T603 unless otherwise specified. Safety Tips: The hydrochloric acid and perchloric acid used in the test are corrosive reagents and should be handled with caution. 4.1 Identification Test
4.1.1 Reagents and Materials
4. 1.1.1 Hydrochloric acid.
4.1.1.2 Ammonia water.
4.1.1.3 Glacial acetic acid.
4.1.1.4 Silver nitrate solution: 17g/L.
4.1.1.5 Platinum wire loop.
4.1.2 Identification method
4.1.2.1 Identification of pyrophosphate
Weigh 0.1g of sample and dissolve it in 10mL of water. Add 1mL of silver nitrate solution to generate a white precipitate. This precipitate is soluble in ammonia water but insoluble in glacial acetic acid.
4.1.2.2 Identification of sodium ion
Weigh 1g of sample and dissolve it in 20mL of water. Dip a platinum wire loop in hydrochloric acid and burn it on a flame until it becomes colorless. Dip the test solution again and burn it on a flame. The flame should be yellow.
4.2 Determination of disodium dihydrogen pyrophosphate content
4.2.1 Summary of method
The sample reacts with zinc sulfate under acidic conditions to generate zinc pyrophosphate precipitate and sulfuric acid. The generated sulfuric acid is titrated with a sodium hydroxide standard titration solution.
4.2.2 Reagents and Materials
4.2.2.1 Hydrochloric acid solution: 1+10.
4.2.2.2 Zinc sulfate solution: 250g/L (adjust to pH 3.8). 4.2.2.3 Anhydrous sodium pyrophosphate.
Sodium pyrophosphate is recrystallized from water three times (preparation method is shown in Appendix A) and placed in platinum. It is burned at 400℃ until the mass is constant. 4.2.2.4 Standard titration solution of sodium hydroxide: c(NaOH) is about 0.1mol/L. Calibration: Weigh 0.3g of anhydrous sodium pyrophosphate (accurate to 0.0002g), place it in a 150mL beaker, add 50mL of water without carbon dioxide to dissolve it, add hydrochloric acid solution while stirring to adjust the solution pH to 3.8, and then follow the steps described in 4.2.4, starting from "add 25mL zinc sulfate solution..." to calibrate. The number of grams of disodium dihydrogen pyrophosphate equivalent to each milliliter of sodium hydroxide standard titration solution (T) is calculated according to formula (1): T = 0.834.5m
Wherein: m-
The mass of anhydrous sodium pyrophosphate, g;
HG 2928--1999
The volume of sodium hydroxide standard titration solution consumed in the calibration, mL; The coefficient of sodium pyrophosphate converted to disodium dihydrogen pyrophosphate. 4.2.3 Instruments and equipment
4.2.3.1 Potentiometric titrator or acidometer.
4.2.3.2 Magnetic stirrer.
4.2.4 Analysis steps
Weigh about 0.3g of sample (accurate to 0.0002g), place it in a 150mL beaker, add 50mL of water without carbon dioxide, and heat to dissolve the sample completely. Use hydrochloric acid solution to adjust the solution to a pH of 3.8 on the acidometer. Add 25 mL of zinc sulfate solution and stir for 3 minutes. Titrate with sodium hydroxide standard titration solution while stirring until the solution has a pH of 3.8, which is the end point. 4.2.5 Expression of analysis results
The content of disodium dihydrogen pyrophosphate (X) expressed as a mass percentage is calculated according to formula (2): TV×100
Where: T-
The number of grams of disodium dihydrogen pyrophosphate equivalent to each milliliter of sodium hydroxide standard titration solution; the volume of sodium hydroxide standard titration solution consumed by the titration test solution, mL; the mass of the sample, g.
4.2.6 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.3%. 4.3 Determination of water-insoluble matter content
4.3.1 Method Summary
After the sample is dissolved in water, it is filtered, washed, dried and weighed. 4.3.2 Instruments and Equipment
4.3.2.1 Glass crucible: filter plate pore size 5μm~15μm. 4.3.2.2 Electric oven: control the temperature at 105℃~110℃. 4.3.3 Analysis Steps
·(2)
Weigh 5g of sample (accurate to 0.01g), place it in a 400mL beaker, add 200mL of water and heat to dissolve, filter it with a glass crucible with a constant mass in advance, and wash it with hot water until the filtrate is neutral. Place the glass crucible together with the water-insoluble matter in an oven at 105℃~110℃ and dry it until the mass is constant.
4.3.4 Expression of analysis results
The water-insoluble content (X2) expressed as a mass percentage is calculated according to formula (3): Xz = ml=m2×100
Wherein: m --
-mass of residue and glass crucible, g;
mass of glass crucible, g;
m——mass of sample, g.
4.3.5 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.3%. 4.4 Determination of arsenic content
(3)
Weigh about 1g of sample (accurate to 0.01g), place in a 100mL beaker, add 20mL of water and 10mL of (1+1) hydrochloric acid solution, heat to dissolve, transfer all to a measuring bottle, add water to a total volume of about 40mL, and operate according to 2.4 of GB/T8450--1987. The standard is to use a pipette to transfer 3mL (1mL solution contains 1μgAs) of arsenic standard solution, and treat it in the same way as the sample. 4.5 Determination of heavy metal content
HG 2928-1999
Weigh about 5g of sample (accurate to 0.01g), place in a 100mL beaker, add 80mL of water, heat to dissolve, transfer to a 100mL volumetric flask, dilute to the mark with water, and mix well. Dry filter with two layers of medium-speed filter paper, discard the first 20ml solution, and pipette 20ml of test solution into a 50ml colorimetric tube. Add a drop of 10g/1 phenolphthalein indicator solution, adjust the solution to neutral with 40g/1 sodium hydroxide solution, add water to a total volume of about 30ml, and operate according to Chapter 6 of GB/T8451-1987. The standard colorimetric solution is 1mL (1m solution contains 10μgPb) of lead standard solution pipetted with a pipette, and treated in the same way as the sample. 4.6 Determination of fluoride content
4.6.1 Summary of the method
In perchloric acid medium, fluorine is separated from the sample by steam distillation. Fluorine forms a blue complex with a mixture of alizarin aminocarboxylic acid complexing agent and lanthanum nitrate. The color of the test solution is compared with that of the standard. 4.6.2 Reagents and materials
4.6.2.1 Perchloric acid.
4.6.2.2 Acetone.
Glacial acetic acid solution: 1+16.
Sodium acetate solution: 250g/L.
Phenolic acid indicator solution: 10g/L.
Silver nitrate solution: 17g/L.
Sodium hydroxide solution: 40g/L.
Sodium hydroxide solution: 4g/L.
Hydrochloric acid solution: 1+10.
4.6.2.10 Alizarin aminocarboxylic acid complexing agent.
Weigh 0.1925g of alizarin aminocarboxylic acid complexing agent, add a small amount of water and sodium hydroxide solution (4.6.2.7) to dissolve, add 0.125g of sodium acetate, adjust the solution to pH 5.0 with glacial acetic acid solution (the solution is red at this time), dilute with water to 500mL, shake well, and store in the refrigerator. When precipitation occurs, it should be prepared again.
4.6.2.11 Lanthanum nitrate solution.
Weigh 0.2165g of lanthanum nitrate, dissolve it with a small amount of glacial acetic acid solution, add water to 450mL, adjust the pH value to 5.0 with sodium acetate solution (check with precision pH test paper), dilute with water to 500mL, and store in a refrigerator. Re-prepare after mold growth. 4.6.2.12 Buffer solution.
Weigh 44g of sodium acetate and dissolve it in 400mL of water, add 22mL of glacial acetic acid, then add glacial acetic acid dropwise to adjust the solution pH value to 4.7 (check with precision pH test paper), and then dilute with water to 500mL. 4.6.2.13 Fluoride standard solution: 1mL of solution contains 0.01mgF. Preparation: Use a pipette to transfer 10mL of fluoride standard solution prepared according to GB/T602, place it in a 100mL volumetric flask, dilute with water to the scale, and shake well. www.bzxz.net
4.6.3 Apparatus and equipment
Fluorine distillation device: see Figure 1.
4.6.4 Analysis steps
Weigh 2.00g of sample (accurate to 0.01g), place in a 250mL three-necked flask (see Figure 1), add a few glass beads, slowly add 10mL perchloric acid, rinse the flask wall with about 8mL water, add 8~10 drops of silver nitrate solution, the thermometer on the bottle stopper should be tightly plugged, and the mercury ball of the thermometer is inserted into the test solution, connect the water vapor generator and the straight condenser, connect the end of the condenser to the glass elbow, and insert the elbow into a 250mL volumetric flask containing 10mL sodium hydroxide solution (4.6.2.8) and 2 drops of phenolic acid indicator solution. Add 500mL of water to the water vapor generator, and add sodium hydroxide solution (4.6.2.7) to make the solution alkaline. Open the screw clamp and heat to near boiling. Close the screw clamp, pass water vapor into the three-necked flask, heat the three-necked flask at the same time, and adjust the amount of water vapor entering so that the temperature rises and remains between 135℃ and 140℃. If the solution in the volumetric flask fades, add an appropriate amount of sodium hydroxide solution (4.6.2.8) until the distillate is about 200mL, stop distillation, and shake. Use sodium hydroxide solution (4.6.2.8) or hydrochloric acid solution to adjust the pH value to 7.0 (check with precision pH test paper), add 2 drops of 814
HG 29281999
hydrochloric acid solution, dilute with water to the scale, and shake. Use a pipette to transfer 25mL of the test solution, place it in a 50mL colorimetric tube, add 5ml of alizarin aminocarboxylic acid complexing agent and 3mL of buffer solution, and mix. Slowly add 5mL of lanthanum nitrate solution and shake. Add 10mL of acetone, add water to 50mL, and leave it at room temperature for 20min. Compared with the standard colorimetric solution, its color should not be darker than the standard colorimetric solution. The standard colorimetric solution is 1.00mL of fluoride standard solution taken with a pipette and treated in the same way as the test solution. 10
1-Water vapor generator (1000mL flask); 2-Safety tube (5mm); 3-Glass tube (5mm); 4, 13, 14-Rubber stopper: 5-Tee and screw clamp; 6-Thermometer 200℃); 7-Three-necked flask (250mL); 8-Glass elbow; 9-Straight condenser (500mm); 10-Glass elbow; 11Volume flask (250mL); 12-Heating jacket or electric furnace Figure 1 Schematic diagram of fluorine distillation device
4.7 Determination of pH value
4.7.1 Summary of method
Immerse the glass electrode and the reference electrode in the test solution to form a primary cell, whose potential is related to the pH value of the solution. The pH value of the solution can be obtained by measuring the potential of the primary cell. 4.7.2 Instruments and equipment
4.7.2.1 Acidity meter: The accuracy is 0.1pH unit. 4.7.2.2 Glass electrode: Soak in water for more than 24 hours before use and store in water. 4.7.2.3 Calomel electrode.
4.7.3 Analysis steps
Weigh about 1g of sample (accurate to 0.01g), place in a 250mL beaker, add 100mL of water to dissolve, and measure the pH value of the solution with a calibrated acidometer.
4.7.4 Allowable difference
Take the arithmetic mean of the parallel determination results as the determination result. The absolute difference of the parallel determination results shall not exceed 0.2pH units. 5 Inspection rules
5.1 All six indicators specified in this standard are factory inspection items. 5.2 Each batch of products shall not exceed 5t.
5.3 Determine the number of sampling units in accordance with the provisions of 6.6 of GB/T6678-1986. Each plastic woven bag is a packaging unit. When sampling, insert the sampler diagonally from the top of each selected packaging bag to 3/4 of the material layer depth, take out no less than 50g of sample with a sampler, mix the sample, and divide it into about 200g by quartering method, and immediately put it into two clean and dry wide-mouth bottles with ground stoppers and seal them. Paste labels on the bottles, indicating: manufacturer name, product name, batch number, sampling date and name of the sampler. One bottle is used for inspection, and the other bottle is kept for three months for future reference. 815
HG2928—1999
5.4 The food additive disodium dihydrogen pyrophosphate shall be inspected by the quality supervision and inspection department of the manufacturer in accordance with the provisions of this standard. The manufacturer shall ensure that each batch of products shipped out of the factory meets the requirements of this standard. If one of the indicators in the inspection results does not meet the requirements of this standard, samples should be taken from twice the amount of packaging for re-inspection. If even one of the indicators in the inspection results does not meet the requirements of this standard, the entire batch of products shall be unqualified. 6 Marking, packaging, transportation and storage
6.1 The packaging bag of the food additive disodium dihydrogen pyrophosphate shall be firmly and clearly marked, including: manufacturer name, address, product name, trademark, "food additive", net content, batch number or production date, shelf life, production license number, this standard promotion number and the "wet-afraid" mark in GB191.
6.2 Each batch of products shipped out of the factory shall be accompanied by a quality certificate, including: manufacturer name, address, product name, trademark, "food additive", batch, batch number or production date, shelf life, production license number, proof that the product quality meets this standard and this standard number. 6.3 Food additive disodium dihydrogen pyrophosphate is packaged in four layers. The inner packaging is a polyethylene plastic film bag for food with a thickness of 0.07mm; the outer packaging is a plastic woven bag. The net content of each bag is 25kg. If the user has special requirements for packaging, the supply and demand parties can negotiate. 6.4 For the packaging of food additive disodium dihydrogen pyrophosphate, the inner bag is tied twice with vinyl rope or a rope of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the edge of the bag, and the opening is sewn with vinyl thread or other threads of equivalent quality at a distance of not less than 15mm from the edge of the bag. The stitches are neat and the stitches are evenly hooked. There are no leaks or skipped stitches. 6.5 Food additive disodium dihydrogen pyrophosphate should be covered during transportation to prevent sun exposure, rain, and moisture. It must not be transported together with toxic and hazardous items. Prevent pollution.
6.6 Food additive disodium dihydrogen pyrophosphate should be stored in a dry warehouse to prevent rain, moisture, and sun exposure. It must not be stored together with toxic and hazardous items. Prevent contamination.
6.7 The shelf life of food additive disodium dihydrogen pyrophosphate is two years under the conditions of packaging, storage and transportation in accordance with this standard. 816
HG2928—1999
Appendix A
(Appendix to the standard)
Preparation method of three-recrystallization sodium pyrophosphate First crystallization: weigh 30g of industrial anhydrous sodium pyrophosphate, place it in a 400mL beaker, add 100mL of water, heat to dissolve, and filter with medium-speed quantitative filter paper. Cool the filtrate in a cold water bath, precipitate crystals, pour out the solution, and wash the crystals twice with a small amount of water. Second crystallization: Heat and dissolve the first crystals with a small amount of water, cool in a cold water bath, precipitate crystals, and pour out the solution. Third crystallization: Recrystallize the second crystals once according to the second crystallization method. If the reagent sodium pyrophosphate decahydrate is used, weigh 80g and operate according to the first and second crystallization methods. 817
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