Foreword
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This standard replaces GB 31604.47-2016 National food safety standard - Food contact materials and articles - Determination of fluorescent brightener in paper, paperboards and paper articles.
The following main changes have been made with respect to GB 31604.47-2016:
——the standard name has been modified as National food safety standard - Food contact materials and articles - Determination of fluorescent substance in paper, paperboards and paper articles;
——the test wavelength of 254nm has been added;
——the expression of the function of standard control gauze has been added; and
——the expression of result judgment has been modified.
National food safety standard -
Food contact materials and articles - Determination of fluorescent substance in paper, paperboards and paper articles
1 Scope
This standard specifies the determination method of fluorescent substances in food contact paper, paperboards and paper articles.
This standard is applicable to the determination of fluorescent substances in food contact paper, paperboards and paper articles.
2 Principle
The presence of fluorescent substances in food contact paper, paperboards and paper articles may be judged by directly observing whether the specimen has obvious fluorescence (i.e., obvious blue or purple fluorescence) under ultraviolet lamp. If there are many discontinuous small spot fluorescence or the fluorescence occurs but is not obvious in the specimen, extract it with alkaline extracting solution, acidify the extracting solution, and then adsorb the fluorescent substances in the extracting solution with gauze. Under the irradiation of ultraviolet lamp, observe whether the gauze has obvious fluorescence to confirm whether the specimen contains fluorescent substances.
3 Reagents and materials
Unless otherwise specified, analytically pure reagents and Class-I water defined in GB/T 6682 are used. The reagents and materials used shall have no fluorescence under ultraviolet lamp.
3.1 Reagents
3.1.1 Acetonitrile (C2H3N): chromatographically pure.
3.1.2 Triethylamine (C6H15N).
3.1.3 Sodium hydroxide (NaOH): guaranteed reagent.
3.1.4 Hydrochloric acid (HCl).
Foreword i
1 Scope
2 Principle
3 Reagents and materials
4 Instruments and equipment
5 Analysis steps