Standard and Test method for Radish red as Food additive

Standard and Test method for Radish red as Food additive

National standards for food safety GB25536--2010 Ministry of Health of the People's Republic of China 2010-12-21

1 Application

This standard is applicable to radish red, which is extracted and refined from red radish (Raphanus sativus L.), in form of dry powder or liquid, dextrin can be added in it, used as a food additive.

2 Normative reference documents

The documents referenced in this standard are essential for the application of this standard. For dated references, date-only versions are applicable to this standard. For undated references, the latest version (including all amendment orders) applies to this standard.

3 Technical Requirements

3.1 Sensory requirements: The requirements shall conform with Table 1.

3.2 Physical and chemical indexes: shall comply with the provisions of Table 2

Appendix A

Analysis Method

A.1 Notes

Unless otherwise noted, the reagents are analytically pure and the water is as specified in GB/T6682 -- 2008 here. Standard titration solution, standard solution, preparation and product for determination of impurities used in the analysis are prepared in accordance with the provisions of GB/T601, GB/T602 and GB/T 603, if no other requirements are indicated. The solution used in this test refers to aqueous solution when the type of solvent used is not indicated.

A.2 Identification

A.2.1 Color Identification

Weigh about 1 g of the sample, dissolve and dilute it to 100 mL it with a buffer solution of Disodium hydrogen phosphate citrate with pH 3.0. The solution should be red to purplish red. Add an appropriate amount of sodium hydroxide solution (40g/L) into the sample solution, and make the sample solution basic, the solution shall change to violet.

A.2.2 Maximum absorption peak

Take some radish red sample solution from A.3, detect by spectrophotometer, and there should be a maximum absorption peak in the range of wavelength 514nm±5nm.

A.3 Determination of color value

A.3.1 Reagents and materials

a) Citric acid

b) Disodium hydrogen phosphate

c)Disodium hydrogen phosphate solution: 0.2 moL/L. Accurately weigh 71.63g disodium hydrogen phosphate (Na₂HPO₄·12H₂O) and fix the volume with water to 1000 mL

d)Citric acid solution :0.1 mol/L. Accurately weigh 21.01g citric acid (C₆H₈0₇·H₂O) and volume it with water to 1000 mL.

e)Disodium hydrogen phosphate citrate buffer (pH 3.0): take 4.11mL of A.3.1c solution and 15.89mL of A.3.1d solution, mix and shake well. If pH is not 3.0, adjust pH to 3.0 with an acid or base

A.3.2 Instruments and Equipments

Spectrophotometer

A.3.3Analytical procedure

Accurately weigh 0.1g~ 0.2g of samples (accurate to 0.000 2g), dissolve it with disodium hydrogen phosphate citrate buffer, transfer it to 100 mL volumetric bottle, add disodium hydrogen phosphate citrate buffer to constant volume to the scale, and shake well. Take this sample solution into a 1 cm colorimetric dish, take buffer solution as blank sample. The absorbance is measured at the maximum absorption wavelength within the range of 514nm±5 nm by spectrophotometer. (The absorbance should be controlled between 0.3 and 0.7, otherwise the concentration of the sample should be adjusted, and then renew the absorbance determination.)

A.3.4 Calculation

The color value is determinated by the following calculation formula (A.1)

E_1cm^1%(514nm±5nm)=A/C *1/100............................................(A.1)

In the calculation formula, E_1cm^1%(514nm±5nm) means: sample solution concentration 1%, in 1cm colorimetric dish, the color value is measured at the maximum absorption wavelength within the range of 514nm±5 nm by spectrophotometer

A means the actual absorbance of the sample liquid determined

C means the the sample solution’s concentration, g/mL.

The experimental results are based on the arithmetic mean of the parallel measurement results. The absolute difference between the two independent measurements obtained under the condition of repeatability is not more than 5% of the arithmetic mean.

A.4 Determination of residue on ignition

A.4.1Analytical procedure

Weigh 2g sample (accurate to 0.001g), place it in the crucible of constant weight treated in advance (for liquid product fully evaporated firstly), at first slowly heated with a small fire to complete carbonization, and then carefully moved it into the high temperature furnace to burn at 600℃ till constant weight.

A.4.2The residue on ignition is determined by following calculation formula (A.2)

X=(m1-m2)/(m3-m2)*100%....................................(A.2)

In the formula, X means the residue weight in percentage

m1 means the weight of crucible and residue on ignition, in grams (g)

m2 means the weight of the crucible, in grams (g)

m3 means the weight of crucible and the sample for test, in grams (g)

The experimental results are based on the arithmetic mean of the parallel measurement results. The absolute difference between the results of two independent measurements obtained under the condition of repeatability is not greater than 5%(powder) or 10%(liquid) of the arithmetic mean.