GB 1886.31-2015National Food Safety Standard -- Food Additives -- Ethyl p-hydroxybenzoate (English PDF)

2.2 Formula

2.3 Relative molecular mass

166.17 (according to 2007 international relative atomic mass)

3.1 Sensory requirements

Sensory requirements shall comply with the requirements of Table 1.

Table 1 Sensory requirements

Project requires test methods Color status odor taste white Crystalline powder Odorless or slight special aroma Bitter, burning hemp Take appropriate sample is placed in a clean, dry white porcelain dish, Concept under natural light Color and state police, smell the smell, taste its flavor

3.2 Physical and Chemical Indicators

Physical and chemical indicators should be consistent with the provisions of Table 2.

Table 2. Physical and chemical indicators

Item Index Test Method Ethylparaben (C9H10O3) content (dry basis), w /% 99.0 ~ 100.5 Appendix A A.4 Melting point/°C 115 ~ 118 Appendix A A.5 Free acid (p-hydroxy benzoic acid), w /% <= 0.55 A.6 in Appendix A Sulfate (SO4 dollars), w /% <= 0.024 Appendix A A.7 Loss on drying, w /% <= 0.50 Appendix A A.8 Residue on ignition, w /% <= 0.05 A.9 in Appendix A Arsenic (As)/(mg/kg) <= 1.0 GB 5009.76 Heavy metals (Pb)/(mg/kg) <= 10.0 Appendix A A.10 Appendix A Testing method A.1 Safety Tips Some test procedures prescribed test method can lead to dangerous situations. The operator shall take appropriate safety and health practices.

A.2 General Provisions this standard reagents and water in the absence of other specified requirements, refer to the three water analytical reagent and GB/T 6682 regulations. test the required standard solution, impurity standard solution, preparations and products, did not indicate when the other requirements according to GB/T 601, GB/T 602 and GB/T 603 provisions prepared. Solution was used in the tests did not indicate what is formulated with solvent, it refers to an aqueous solution.

A.3 Identification Test A.3.1 Reagents and materials A.3.1.1 sodium hydroxide solution. 40g/L.

A.3.1.2 barium chloride solution. 250g/L.

A.3.1.3 sodium hydroxide solution. 80g/L.

A.3.1.4 sulfuric acid solution. 117.

A.3.1.5 iodine solution. 12.7g/L.

A.3.2 Identification method A.3.2.1 Weigh about 0.5g sample accurate to 0.01g, add 10mL of sodium hydroxide solution (A.3.1.1) boiled 30min, evaporated to about 5mL, cooling, adding sulfuric acid into the acid solution, filtered, washed the precipitate with barium chloride solution to the filtrate turbidity test does not occur, then the precipitate at 105 °C ± 2 °C drying 1h, according to GB/T 617 Determination of the melting point, the final melt temperature should be in the range of 213 °C ~ 217 °C.

A.3.2.2 Weigh 0.5g sample accurate to 0.01g, add 5mL sodium hydroxide solution (A.3.1.3), placed in boiling water bath for 5min, add 6mL sulfuric acid solution, cooled, filtered and the filtrate was added 5mL sodium hydroxide solution (A.3.1.3), warmed to 50 °C, then adding iodine dissolved 5mL Solution, methyl iodide appears three odor, followed by a precipitate.

A.4 Determination of Ethylparaben (C9H10O3) content (dry basis) of A.4.1 principle of the method Sample with an amount of sodium hydroxide saponification reaction, excess sodium hydroxide with sulfuric acid standard titration solution titration, pH meter indication end. According to the consumption of sulfuric acid standard titration solution volume calculation Ethylparaben content.

A.4.2 Reagents and materials A.4.2.1 sodium hydroxide solution. 40g/L.

A.4.2.2 buffer solution. 25 °C when, pH 4.01 and 6.86 buffer solution, according to GB/T 9724 in preparation 4.2 and 4.3.

A.4.2.3 sulfuric acid standard titration solution. c 12H2SO4 ÷ = 1mol/L.

A.4.3 Instruments and Equipment pH meter. accuracy pH0.1.

A.4.4 Analysis step

A.4.4.1 according to GB/T 9724 for pH meter debugging.

A.4.4.2 Weigh about 2g samples were dried at 80 °C ± 2h after 2 °C, accurate to 0.0002g, placed in 250mL bottle of iodine, quasi Sodium hydroxide solution was added 40mL indeed, slowly heated to boiling under reflux for 1h, cooled to room temperature, quantitatively transferred to a beaker, moves to advance with a pH = 6.86 buffer solution, a good tune on pH meter, with sulfuric acid standard titration solution was titrated to pH 6.50 and stabilize 30s, is the end.

A.4.4.3 measured at the same time, according to the same procedure and the determination of the sample without using the same amount of reagent blank test solution.

A.4.5 Calculation Results Ethylparaben (C9H10O3) content mass fraction w1, according to equation (A.1) Calculated.

V1-V2

1000 × c × M

m × 100%

Where.

V1 --- blank test volume consumption standards sulfuric acid titration solution (A.4.2.3), expressed in milliliters (mL);

Volume V2 --- sample consumption standards sulfuric acid titration solution (A.4.2.3), expressed in milliliters (mL);

1000 --- milliliters and liters of conversion factor;

C --- concentration of sulfuric acid standard titration solution, expressed in moles per liter (mol/L);

The molar mass M --- ethylparaben, in units of grams per mole (g/mol), [M (C9H10O3) = 166.2];

M --- the quality of the sample, in grams (g).

Take two parallel determination results of the arithmetic average of the measurement results, the results of two parallel determination of the absolute difference is not more than 0.2%.

Determination of the melting point A.5 A.5.1 capillary method (Arbitration Act) Conducted in accordance with GB/T 617's. In the end of melting temperature as a measurement result. Arithmetic mean of two parallel determination results for the determination as a result, the results of two parallel determination of the absolute difference is not more than 0.3 °C.

A.5.2 digital melting point apparatus Act A.5.2.1 instruments and equipment Digital Melting Point. temperature control accuracy of ± 0.5 °C.

A.5.2.2 analysis step Operating instructions by the melting point apparatus is adjusted to correct melting point apparatus. Adjust the instrument temperature to 112 °C. The sample was finely dried loaded Clean and dry the melting point of the tube, taking about dried hollow glass tube 800mm upright on the glass or porcelain plate, containing the melting point of the sample tube which drop more than 15 times, until the melting point of the sample tube to tightening 3mm ~ 5mm high or the appropriate height, the temperature of the instrument to be stable, the the melting point of the sample tube containing the sample is inserted into the hole, adjust the zero, at a rate of 1 °C/min heating up, after a few minutes the instrument displays incipient melting of the sample and the final Melting temperature. In the end of melting temperature as a measurement result.

Take two parallel determination results of the arithmetic average of the measurement results, the results of two parallel determination of the absolute difference is not more than 0.5 °C.

A.6 free acid (p-hydroxy benzoic acid) Determination A.6.1 Reagents and materials A.6.1.1 sodium hydroxide standard titration solution. c (NaOH) = 0.1mol/L.

A.6.1.2 methyl red indicator solution. 1g/L.

A.6.2 Analysis step

Weigh 0.75g sample, accurate to 0.01g, 15mL placed in hot water heated to about 80 °C 1min, cooling, filtration, of 10mL Solution, add 2 drops of methyl red indicator solution, titration with sodium hydroxide standard titration solution to yellow, stable 30s is the end, the consumption of sodium hydroxide standard Volume quasi titration solution should not exceed 0.20mL, is equal to the free acid content of less than 0.55%.

A.7 Sulfate (SO4 meter) measurement A.7.1 Reagents and materials A.7.1.1 hydrochloric acid solution. 13.

A.7.1.2 barium chloride solution. 250g/L.

A.7.1.3 sulphate (SO4) standard solution. 0.1mg/mL.

Configuring A.7.1.4 Standard solution. Take 0.96mL sulphate (SO4) 50mL colorimetric tube, add 5mL hydrochloric acid solution and standard solution in 3mL barium chloride solution, shake, place 10min.

A.7.2 Analysis step

Weigh 1.0g sample to the nearest 0.01g, add water 100mL shaken thoroughly mixed, heated 5min, cooling, water was added to 100mL, Filtered and the filtrate 40mL in 50mL colorimetric tube, add 5mL hydrochloric acid solution and 3mL barium chloride solution, shake, place 10min, the Turbidity was not greater than the standard, namely Sulfate (SO4) mass fraction is less than equal to 0.024%.

A.8 Determination of loss on drying A.8.1 Analysis step Weigh 2g samples, accurate to 0.0002g, has been placed in pre-dried to a constant 80 °C ± 2 °C 45mm diameter quality high 25mm weighing bottle, distribution, ± 2 °C 2h and dried at 80 deg.] C, removed and cooled to room temperature, and weighed.

A.8.2 Calculation Results Loss on drying mass fraction w2, according to equation (A.2) Calculated.

m1-m2

100% (A.2)

Where.

Mass m1 --- prior to drying of the sample, in grams (g);

Quality, unit m2 --- after drying the sample in grams (g).

Take two parallel determination results of the arithmetic average of the measurement results, the results of two parallel determination of the absolute difference is not more than 0.05%.

A.9 Determination of residue on ignition Conducted in accordance with GB/T 9741's. Measured, weighed 5g samples, accurate to 0.0002g. Ignition temperature of 500 °C ± 50 °C.

Take two parallel determination results of the arithmetic average of the measurement results, the results of two parallel determination of the absolute difference is not more than 0.01%.

A.10 heavy metals (Pb) Determination A.10.1 reagents and materials A.10.1.1 acetone.

A.10.1.2 sodium sulfide solution. Weigh sodium sulfide 5g, accurate to 0.01g, water 10mL and 30mL glycerol mixed and dissolved. This solution makes with a period of two weeks.

A.10.1.3 acetic acid solution. 1 -> 20.

A.10.1.4 Lead (Pb) standard solution. 10µg/mL.

A.10.2 Analysis steps Weigh 2.0g sample to the nearest 0.001g, in 50mL colorimetric tube, add 25mL acetone dissolved, add 2mL acetic acid solution, washed with water Diluted to 50mL, add 2 drops of sodium sulfide solution, shake, in the dark place 10min, the color was not deeper than the standard.

Configure standard solution is to draw 2.00mL lead (Pb) standard solution is diluted with water to 50mL, add 2 drops of sodium sulfide solution and shake.