This standard specifies two methods for the determination of thiamine content in feed, namely by fluorescence spectrophotometry and high-performance liquid chromatography.
Method 1 of this standard is applicable to the determination of thiamine in feedstuffs, formula feed and concentrate. The quantitative limit of Method 1 is 1 mg/kg (this method is not applicable in the presence of adsorbent thiamine or interfering substances that affect thiochrome fluorescence). Thiamine determined by this method includes the sum of endogenous and additive amounts.
Method 2 of this standard is applicable to the determination of thiamine in compound premix and vitamin premix. The detection limit of Method 2 is 3 mg/kg, and the quantitative limit is 15 mg/kg.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 6682 Water for Laboratory Use — Specifications and Test Methods
GB/T 14699.1 Animal Feeding Stuffs — Sampling
GB/T 20195 Animal Feeding Stuffs —Preparation of Test Samples
3 Method 1: Fluorescence Spectrophotometry
3.1 Principle
GB/T 14700-2018 The following standards are cited：
