GB 5009.36-2023 National food safety standard - Determination of cyanide in food
1 Scope
This standard specifies methods for determination of cyanide in foods.
Method I Spectrophotometry is applicable to the determination of cyanide in distilled alcoholic drinks and its integrated alcoholic drinks, edible alcohols, cassava powder, packaged drinking water and mineral water.
Method II Gas chromatography (GC) and Method III Gas chromatography-mass spectrometry (GC-MS) are applicable to the determination of cyanide in Baijiu, edible alcohols, grains, packaged drinking water and mineral water.
Method IV Ion chromatography (IC) is applicable to the determination of cyanide in distilled alcoholic drinks and its integrated alcoholic drinks, edible alcohol, packaged drinking water, mineral water and almond-based beverages.
Method V Flow injection (FI)/sequential injection (SI) -spectrophotometry is applicable to the determination of cyanide in distilled alcoholic drinks and its integrated alcoholic drinks, edible alcohols, packaged drinking water and mineral water.
Method I Spectrophotometry
2 Principle
The specimens are either heated under alkaline conditions to remove organics with high-boiling points or heated and distilled under acidic conditions. After being dissolved or absorbed by sodium hydroxide solution, cyanide is converted into cyanogen chloride with chloramine-T at pH = 7.0, and then reacted with isonicotinic acid-pyrazolone to generate a blue color, and finally quantified by comparison with the standard series.
3 Reagents and materials
Unless otherwise specified, analytical-grade reagents and Grade III water as specified in GB/T 6682 are used for the purpose of this method.
3.1 Reagents
3.1.1 Absolute ethanol(C2H6O).
3.1.2 Zinc acetate (C4H6O4Zn).
3.1.3 Tartaric acid (C4H6O6).
3.1.4 Sodium hydroxide (NaOH).
3.1.5 Monopotassium phosphate (KH2PO4).
3.1.6 Disodium phosphate (Na2HPO4).
3.1.7 Glacial acetic acid (C2H4O2): >99.5%.
3.1.8 Isonicotinic acid (C6H5O2N).
3.1.9 Pyrazolone (C10H10N2O).
3.1.10 Chloramine-T (C7H7SO2NClNa·3H2O).
3.1.11 Methyl orange (C14H14O3N3SNa).
3.1.12 Phenolphthalein (C20H14O4).
3.2 Preparation of reagents
Foreword i
1 Scope
Method I Spectrophotometry
2 Principle
3 Reagents and materials
4 Instruments and apparatus
5 Analysis procedure
6 Expression of analysis results
7 Accuracy
8 Miscellaneous
Method II Gas chromatography
9 Principle
10 Reagents and materials
11 Instruments and apparatus
12 Analysis procedure
13 Expression of analysis results
14 Accuracy
15 Miscellaneous
Method III Gas chromatography-mass spectrometry
16 Principle
17 Reagents and materials
18 Instruments and apparatus
19 Analysis procedure
20 Expression of analysis results
21 Accuracy
22 Miscellaneous
Method IV Ion chromatography
23 Principle
24 Reagents and materials
25 Instruments and apparatus
26 Analysis procedure
27 Expression of analysis results
28 Accuracy
29 Miscellaneous
Method V Flow injection/sequential injection-spectrophotometry
30 Principle
31 Reagents and materials
32 Instruments and apparatus
33 Analysis procedure
34 Expression of analysis results
35 Accuracy
36 Miscellaneous
Annex A Reference conditions for headspace analysis
Annex B Standard gas chromatogram of cyanogen chloride
Annex C Setting of ion chromatography conditions and examples of standard chromatogram
Annex D Determination spectrum of cyanide ion in distilled alcoholic drinks and its integrated alcoholic drinks by flow injection/sequential injection
