GB 1886.171-2016National Food Safety Standard -- Food Additives - 5′-Flavor Nucleotides Disodium (English PDF)

2.1 Disodium 5'-inosinic acid (IMP)

2.1.1 Formula

C10H11N4Na2O8P · nH2O

2.1.2 Structure

2.1.3 Relative molecular mass (anhydrous)

392.17 (according to 2011 international relative atomic mass) 2.2 5'-disodium guanylate (GMP)

2.2.1 Formula

C10H12N5Na2O8P · nH2O

2.2.2 Structure

2.2.3 Relative molecular mass (anhydrous)

407.18 (according to 2011 international relative atomic mass)

3.1 Sensory requirements

Sensory requirements shall comply with the requirements in Table 1.

Table 1 Sensory requirements

Project requires test methods White or white color Crystalline state or crystalline powder Proper amount of sample is placed in a clean, dry porcelain dish, natural light the observed color and state

3.2 Physical and Chemical Indicators

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

A.2 flavor nucleotides disodium content (dry basis), the mixing ratio of IMP and GMP was measured mixing ratio A.2.1 Reagents and materials Hydrochloric acid solution. amount of 0.9mL of hydrochloric acid, 1000mL water was slowly injected.

A.2.2 Instruments and Equipment UV spectrophotometer (band width. 1nm, wavelength accuracy. ± 2.0nm, wavelength repeatability. ± 1.0nm, stray light. <= 0.02%).

A.2.3 Analysis step

Preparation of sample solution A.2.3.1 0.4 g of a sample was weighed (accurate to 0.0001g) in 100mL beaker, dissolved with appropriate amount of water and dilute to 250 mL, shake, spare.

5.0 mL of the solution suction, the solution was diluted with hydrochloric acid and dilute to 250 mL, shake, a sample solution for use.

A.2.3.2 Determination the sample solution was injected into 1cm Shi Ying cuvette, a solution of hydrochloric acid as a reference solution, UV spectrophotometer at 250nm, Absorbance was measured at 280nm.

A.2.4 calculation results A.2.4.1 flavor nucleotides disodium was calculated content (dry basis) of Disodium flavor nucleotides content (dry basis) the mass fraction w1, according to formula (A.1) is calculated.

(A-1.463 × B) × 254.55 (7.976 × BA) × 47.769 m × 5 × 100-w4 × 100% (A.1) where.

A --- sample solution measured at 250nm absorbance;

B --- sample solution measured at 280nm absorbance;

--- m sample weight of the sample in grams (G);

5 --- volume conversion factor;

100 --- conversion factor;

--- W4 of the sample weight loss on drying,%;

1.463,254.55,7.976,47.769 dual wavelength absorbance measurement ---, according to Beer's law, equation derivation for generating Coefficients.

The test result to the arithmetic mean of replicates results. Obtained in two independent determination results under repeatability conditions of absolute difference Value is not more than 1% of the arithmetic mean. Results accurate to one decimal place.

Calculation A.2.4.2 IMP and GMP mixing ratio of the mixing ratio of IMP content of w2, calculated according to equation (A.2).

A-1.463 × B () × 342.18 m × 5 × 100% (A.2) Mass fraction of GMP w3, calculated according to formula (A.3).

7.976 × BA () × 62.55 m × 5 × 100% (A.3) of formula (A.2), the formula (A.3) in which.

A --- sample solution measured at 250nm absorbance;

B --- sample solution measured at 280nm absorbance;

--- m sample weight of the sample in grams (G);

5 --- volume conversion factor;

--- 1.463,342.18,7.976,62.55 measuring the absorbance at dual wavelength, according to Beer's law, the mathematical expression generated during derivation coefficient.

It mixing ratio X1, according to formula (A.4) is calculated.

w2 w3 ×

100% (A.4)

GMP mixing ratio X2, according to formula (A.5) Calculated.

w2 w3 ×

100% (A.5)

Of formula (A.4), formula (A.5) in which.

--- w2 of the mass fraction of IMP the sample,%;

--- W3 sample mass fraction of GMP,%;

The test result to the arithmetic mean of replicates results. Obtained in two independent determination results under repeatability conditions of absolute difference Value is not more than 1% of the arithmetic mean. Results accurate to one decimal place.

A.3 measured light transmittance (5% aqueous solution) A.3.1 Instruments and Equipment Spectrophotometer.

A.3.2 Analysis step

1g sample was weighed (accurate to 0.0001g), was dissolved in 20mL of water, shake well. The solution was placed in the sample cuvette of 1cm to Water as blank, the light transmittance measured with a spectrophotometer at a sample solution of 430 nm, the readings are recorded.

The test result to the arithmetic mean of replicates results. Obtained in two independent determination results under repeatability conditions of absolute difference Value is not greater than 0.5% of the arithmetic mean.

Determination A.4 pH (5% aqueous solution) A.4.1 Instruments and Equipment PH meter.

A.4.2 Analysis step

1g sample was weighed (accurate to 0.0001g), was dissolved in 20mL of water, the pH of the sample solution was measured by pH.

The test result to the arithmetic mean of replicates results. Obtained in two independent determination results under repeatability conditions of absolute difference is not greater than 0.2.

Determination of nucleotide A.5 Other A.5.1 Reagents and materials A.5.1.1 developing solution. saturated aqueous ammonium isopropanol = 79,219.

A.5.1.2 chromatography filter.

A.5.2 Instruments and Equipment A.5.2.1 UV analyzer.

A.5.2.2 micro-syringe.

A.5.3 Analysis step

Sample Weigh 1.0g, dissolved in water and dilute to 100mL, chromatography paper spotted with 10.0µL, expand to expand solution for about 30cm, Drying (or drying) the filter paper is observed at 254nm in a UV analyzer.

A.5.4 results found

If only presents IMP, GMP two spots, it is determined by testing.

Determination of amino acid A.6 A.6.1 Reagents and materials Ninhydrin solution. Take ninhydrin 0.5g, was dissolved in ethanol and brought to 100mL.

A.6.2 Instruments and Equipment Water bath.

A.6.3 Analysis step

Sample weighed 0.1g, dissolved in water and dilute to 100mL, after shaking the sample was drawn 5mL, ninhydrin solution was added 1mL, in boiling Water bath heated 3min.

A.6.4 results found

Solution does not color, it is determined by experiments.

A.7 Determination of ammonium salt A.7.1 Reagents and materials A.7.1.1 magnesium oxide.

A.7.1.2 red Shi Rui paper.

A.7.2 Analysis step

0.1g sample was weighed in a test tube, and 1mL of water was added 50mg of magnesium oxide, red Shi Rui paper moistened with water, will be linked into a test tube , The tube was heated in a boiling water bath for 5min.

A.7.3 results found

No litmus color, is determined by experiments.