Abstract:

[Objective] The present study was conducted to establish a high performance liquid chromatography （HPLC） method for simultaneous determination of 8 fat-soluble vitamins （vitamin A, vitamin D₂, vitamin D₃, α-tocopherol, β-tocopherol, γ-tocopherol, δ-tocopherol and vitamin K₁） and the natural pigment β-carotene in Mongolian traditional cheese. [Method] The cheese samples were extracted with absolute ethanol and then enzymatically hydrolyzed. After extraction with n-hexane and concentration by rotary evaporator, the products were redissolved and filtered. Subsequently, they were separated by Agilent poroshell 120 EC-C18 chromatographic column （150 mm×4.6 mm, 4 μm） using the mobile phases of methanol and water （V/V=95∶5）. FLD and VWD were used as detectors, and the external reference method was used for quantification. [Result] The standard curves of vitamin A, α-tocopherol, β-tocopherol, γ-tocopherol, δ-tocopherol, vitamin K₁ and β-carotene all exhibited ideal linear relation in the concentration range of 0.1-1.0 μg/mL （R²>0.998）, and those of vitamin D₂ and vitamin D₃ had good linear relation in the concentration range of 0.05-1.00 μg/mL （R²>0.998）. [Conclusion] The established HPLC method has the advantages of simplicity, rapidity, high sensitivity, high recovery rate and short detection time, which provides technical support for the rapid detection of multiple fat-soluble vitamins and natural pigments in Mongolian traditional dairy products.

Key words: high performance liquid chromatography method, traditional cheese, fat-soluble vitamins, β-carotene