GB 1903.54-2021National Food Safety Standard - Food Nutrient Fortifier - Choline Bitartrate (English PDF)

2.1 Chemical name

(2-Hydroxyethyl) trimethylamine-tartrate

2.2 Structural formula

2.3 Molecular formula

C9H19NO7

2.4 Relative molecular mass

253.25 (according to the international relative atomic mass in 2018)

3.1 Sensory requirements

Sensory requirements shall be in accordance with Table 1.

A.1 General provisions

The reagents and water that are used in this Standard, when no other requirements are specified, refer to analytical reagents and grade-III water which is specified in GB/T 6682. The standard solution, the standard solutions, preparations and products for impurity determination, which are used in the test, are all prepared in accordance with the provisions of GB/T 601, GB/T 602, and GB/T 603, when no other requirements are specified. The solution used in the test, if not indicated which solvent is used, refers to aqueous solution.

A.2 Identification test

A.2.1 Infrared spectrum test

Use potassium bromide smear method, to measure the infrared absorption spectrum in accordance with GB/T 6040; the measured infrared spectrum shall be consistent with the standard substance spectrum of choline bitartrate (see Appendix B).

A.2.2 Precipitation reaction

A.2.2.1 Reagents and materials

Iodine solution: Weigh 14 g of iodine; dissolve it in 100 mL of water that contains 36 g of potassium iodide; add 3 drops of hydrochloric acid; add water to dilute to 1 000 mL; mix well.

A.2.2.2 Analysis steps

Weigh 0.5 g of the sample; dissolve it in 2 mL of iodine solution, and it immediately produces a reddish-brown precipitate. After adding 5 mL of 40 g/L sodium hydroxide solution, the precipitate dissolves and the solution becomes clear yellow. Heat the solution, and it produces a light-yellow precipitate.

A.2.3 Color reaction

A.2.3.1 Reagents and materials

A.2.3.1.1 Potassium ferrocyanide solution

Weigh 2 g of potassium ferrocyanide [K4Fe(CN)6·3H2O]; dissolve it in 100 mL of water. This solution is prepared for immediate use.

A.3

V1 - the volume of perchloric acid standard solution that is consumed by the titration of the sample solution, in milliliters (mL);

V2 - the volume of perchloric acid standard solution that is consumed by the titration of the blank solution, in milliliters (mL);

M - the molar mass of choline bitartrate, in grams per mole (g/mol), [M(C9H19NO7) = 253.25];

1 000 - volume conversion factor; m - sample mass, in grams (g). w - the moisture content of the sample, in grams per hundred grams (g/100 g).

The test result is based on the arithmetic mean of the parallel determination results. The absolute difference between two independent determination results that are obtained under repeatability conditions is not more than 0.5%.

A.4 Determination of ignition residue

A.4.1 Reagents and materials

Sulfuric acid

A.4.2 Instruments and apparatuses

A.4.2.1 Balance: sensitivity of 0.1 mg.

A.4.2.2 Crucible.

A.4.2.3 High temperature furnace.

A.4.2.4 Desiccator.

A.4.3 Analysis steps

Take about 2 g of the sample (accurate to 0.000 1 g); put it into a crucible that has been ignited to a constant weight; slowly ignite on an electric furnace until it is completely carbonized; cool to room temperature. Add 0.5 mL of sulfuric acid to wet it; heat at low temperature until sulfuric acid vapor completely escapes. Then, move it into a high-temperature furnace and burn it at 800 °C ± 25 °C until it is completely ashed. Take out the crucible; move it to a desiccator; let it cool to room temperature; weigh it accurately; then, burn it in a high-temperature furnace until it has a constant weight. Constant weight means that the difference between the two weighings does not exceed 0.5 mg. The carbonization operation is carried out in a fume hood. […]