GB 14751-2010National food safety standards of food additives vitamin B1 (thiamine hydrochloride) (English PDF)

Foreword

This standard replaces GB 14751-1993 "Food additive vitamin B1 (thiamine hydrochloride)." this standard compared with GB 14751-1993, the main changes are as follows.

- Added arsenic indicators;

- Cancel the heavy metal indicator, an increase of lead indicators <=2mg/kg.

Appendix A of this standard is a normative appendix.

The standard replaces the previous editions.

--GB 14751-1993.

National Food Safety Standard Food additive vitamin B1 (thiamine hydrochloride)

1 Scope

This standard applies to by chemical synthesis of food additives, vitamin B1 (thiamine hydrochloride).

2 Normative references

The standard file referenced in the application of this standard is essential. For cited documents with dates, only the date of Version applies to this standard. For undated references, the latest edition (including any amendments) applies to this standard.

3 Chemical name, molecular formula, molecular mass and structural formula

4 Technical Requirements

4.1 Sensory requirements. comply with Table 1.

Table 1 Sensory requirements

Project requires test methods Color White take appropriate sample is placed in a clean, dry white porcelain dish, in natural light, observe its color and texture, Smell the odor.

Faint odor usually has a special smell Organization state crystal or crystalline powder Melting point of about 248 °C melting and decomposition

4.2 Physical indicators. to comply with Table 2.

Table 2. Physical and chemical indicators

Item Index Test Method Vitamin B1 (to C12H17ClN4OS - HCl meter, dry basis), w /% 98.5 ~ 101.5 Appendix A A.4 pH (25 g/L solution) 2.7 ~ 3.4 in Appendix A A.5 Color of the solution through the test A.6 in Appendix A Nitrate (20 g/L solution) by testing in A.7 in Appendix A Loss on drying, w /% <= 5.0 Appendix A A.8 Residue on ignition, w /% <= 0.1 A.9 in Appendix A Lead (Pb)/(mg/kg) <= 2 GB 5009.12 Arsenic (As)/(mg/kg) <= 2 Appendix A A.10 Appendix A (Normative) Testing method A.1 Safety Tips Reagents The standard test methods used for toxic or corrosive, according to the relevant provisions of the operation, the operation need to be careful.

If splashed on the skin should immediately wash with water, severe cases should be treated immediately. When using a volatile acid, to be carried out in a fume hood.

A.2 General Provisions the reagents used in this standard, unless otherwise noted, only in the analysis confirmed analytically pure reagents and GB/T 6682-2008 in Regulation Given three water.

Standard Solution, Test Method for preparation and products required, did not indicate when the other requirements, according to GB/T 601, GB/T 603 Provisions prepared.

A.3 Identification Test A.3.1 Reagents and materials A.3.1.1 n-butanol.

A.3.1.2 manganese dioxide.

A.3.1.3 sulfuric acid.

A.3.1.4 sodium hydroxide solution. 40 g/L.

A.3.1.5 ferricyanide solution. 100 g/L.

A.3.1.6 starch indicator solution. 5 g/L.

A.3.1.7 potassium iodide starch paper. Take the filter paper dipped in starch indicator solution containing 0.5 g of potassium iodide in 100 mL of fresh, wet after Remove dried, that is.

A.3.2 Identification method Color identification A.3.2.1 sulfide A.3.2.1.1 principle of the method Vitamin B1 (thiamine) in an alkaline solution, easily oxidized to ferricyanide sulfur dye, sulfur dye soluble in n-butanol, it was strong blue fluorescence.

A.3.2.1.2 analysis step Weigh about 5 mg laboratory samples, add 2.5 mL of sodium hydroxide solution dissolved, add 0.5 mL of potassium ferricyanide solution and 5 mL n Butanol, shake vigorously 2min, placed so hierarchical, top layer of alcohol was strong blue fluorescence; adding acid into the acid, the fluorescence disappears;

Coupled with a base made basic, and fluorescence show.

A.3.2.2 Identification of chlorides Weigh about 0.5 g laboratory samples, home dry test tube, add 0.5 g of manganese dioxide, mixing, wet sulfuric acid heated slowly, namely Produce chlorine, potassium iodide starch paper to make moist blue color.

A.4 Determination of vitamin B1 A.4.1 principle of the method Primary amines and quaternary ammonium groups of vitamin B1 (thiamine) has become the molecule contains a basic salt in a non-aqueous solution (kept in mercuric acetate Below) can be used with perchloric acid effect. Vitamin B1 content is calculated according to the amount consumed perchloric acid.

A.4.2 Reagents and materials A.4.2.1 glacial acetic acid.

A.4.2.2 mercuric acetate solution. 50 g/L of glacial acetic acid solution.

A.4.2.3 perchloric acid standard titration solution. c (HClO4) = 0.1 mol/L.

A.4.2.4 QUINALDINIC red - methylene blue mixed indicator solution. 0.3 g QUINALDINIC red, 0.1 g methylene blue, add methanol to 100 mL.

A.4.3 Analysis step

Take about 150 mg laboratory samples, accurate to 0.000 1 g, add 20 mL of glacial acetic acid, in the micro hot water bath sonication, coolish, 5 mL of mercuric acetate solution, 2 drops QUINALDINIC red - methylene blue mixed indicator solution, titration with perchloric acid standard solution titration to sky blue, strong Strong shaking, 30s does not fade as the end point. The results and titration with blank test correction.

A.4.4 Calculation Results Vitamin B1 (thiamine hydrochloride, to C12H17ClN4OS · HCl meter) mass fraction 1w, expressed in%, according to formula (A.1) Calculated.

() 100%

(1) 1000

VV c Mw

- × × = ×× - × (A.1) where.

V - Numerical sample consumption perchloric acid standard titration solution volume in milliliters (mL);

0V - Numerical blank test perchloric acid standard titration solution consumption volume in milliliters (mL);

c - the value of the actual concentration of perchloric acid standard titration solution, expressed in moles per liter (mol/L);

m - mass of the laboratory sample values in grams (g);

2w --A.8 measured value loss on drying,%;

M - value of vitamin B1 (1/2C12H17ClN4OS · HCl) molar mass of the units of grams per mole (g/mol) (M = 168.6).

Take the arithmetic mean of the parallel determination results of the measurement results, the two parallel determination results allow absolute difference less than 0.3%.

A.5 pH measurement

Weigh about 0.50 g laboratory samples, accurate to 0.01 g, add 20 mL of water dissolved, with acidimeter pH.

A.6 Determination of color of the solution A.6.1 Reagents and materials Potassium dichromate solution. take 4.90 g of potassium dichromate, add water to dissolve into a 1000 mL, shake, that was.

A.6.2 Analysis step

Weigh about 1.0 g laboratory samples, accurate to 0.01 g, placed Nessler colorimetric tube, add 10 mL of water was dissolved, the solution should be colorless, such as color, with the same volume of control solution (potassium dichromate solution take 1.5 mL, add water to make into a 1000 mL), not deeper.

Determination A.7 nitrate A.7.1 Reagents and materials A.7.1.1 sulfuric acid.

A.7.1.2 ferrous sulfate solution. 80 g/L.

A.7.2 Analysis step

Weigh about 1.0 g laboratory samples, accurate to 0.01 g, add 50 mL of water dissolved in 2 mL take a test tube, add 2 mL of sulfuric acid, Cooling, along the wall slowly added 2 mL solution of ferrous sulfate, two-junction can not be a brown ring.

A.8 Determination of loss on drying A.8.1 Analysis step Weigh about 1.0 g laboratory samples, accurate to 0.000 1 g, has been placed at 105 °C ± 2 °C drying to constant weight flat weighing bottle, at 105 °C ± 2 °C oven dried to constant weight.

A.8.2 Calculation Results Vitamin B1 (thiamine) Loss on drying mass fraction 2w and its value is expressed in%, according to formula (A.2) Calculated.

2 100%

m mw

Where.

1m - the value of the total mass of the laboratory sample before drying and weighing bottles in grams (g);

2m - After drying the value of the total mass of the laboratory sample and weighing bottle in grams (g);

m - mass values laboratory sample in grams (g).

Take the arithmetic mean of the parallel determination results of the measurement results, the two parallel determination results allow absolute difference less than 0.1%.

A.9 Determination of residue on ignition A.9.1 principle of the method Sample by adding sulfuric acid sulphate after ignition of the left, with the weight method.

A.9.2 Analysis step

It weighs about 1.0 g laboratory samples, accurate to 0.000 1 g, placed in a burned to constant weight porcelain crucible at 750 °C ± 50 °C, with Small fire slowly heated to completely carbonized, after cooling, add 0.5 mL sulfuric moist, low-temperature heating to sulfuric acid vapor divisible shifted into high temperature Furnace to burning at 750 °C ± 50 °C constant weight.

A.9.3 Calculation Results Vitamin B1 (thiamine) burning residue mass fraction 3w and its value is expressed in%, according to formula (A.3) Calculated.

m mw

Where.

3m - the value of the total mass of the crucible and residue, in grams (g);

4m - Numerical crucible mass in grams (g);

m - mass of the laboratory sample values in grams (g).

Take the arithmetic mean of the parallel determination results of the measurement results, the results of two parallel determination of the absolute difference is not more than 0.02%.

A.10 Determination of Arsenic A.10.1 principle of the method in strongly acidic solution, the sample can be reduced to metallic zinc arsenic into arsine regenerate brown and mercuric bromide paper role Yellow compound. Samples with arsenic standard solution using the same method of treating the resulting brown compound compared to the sample in order to check the arsenic salt limit.

A.10.2 Analysis steps Weigh 5.0 g ± 0.01 g laboratory samples weighed 10 mL ± 0.05 mL limit of arsenic standard solution (per 1 mL solution is equivalent to 1µg Arsenic), respectively, after pressing GB/T 5009.76-2003 first dry ashing method 5.2.2 Treatment of samples, according to the second law Gutzeit assay samples.

Arsenic in the sample can not be deeper than the standard spot Gutzeit.