关键词: 双歧杆菌; 抑菌活性; 琼脂扩散法; 无细胞上清液; 母乳寡糖

Abstract: A high-performance liquid chromatography method was developed to determine the contents of 5-hydroxymethylfurfural and furfural in liquid milk. The samples were extracted with oxalic acid solution in a boiling water bath, then the protein and fat were precipitated by adding trichloroacetic acid solution. The supernatant was separated on an XDB-C18 column (4.6 mm × 250 mm, 5 μm) using 10% acetonitrile solution as the mobile phase. The analytes were detection with an ultraviolet detector and quantified by the external standard method. The experimental results showed that the correlation coefficient of 5-hydroxymethylfurfural was 0.999 8, with a spiked recovery ranging from 84.6% to 94.3%, a limit of detection (LOD) of 0.005 mg/kg, and a coefficient of variation (CV) of 0.15% to 0.36%. For furfural, the correlation coefficient was 0.999 4, with a spiked recovery rate ranging from 73.7% to 92.0%, a LOD of 0.005 mg/kg, and a CV of 0.95% to 1.54%. This method is characterized by simple operation, low cost, and excellent separation performance, and it is suitable for the quantitative analysis of 5-hydroxymethylfurfural and furfural in liquid milk, providing technical support for the quality control and process optimization of dairy products.

Key words: furfural; 5-hydroxymethylfurfural; high-performance liquid chromatography; liquid milk