Vitamin E Extraction and Quantification in Cake

Vitamin E in cake samples was extracted and determined referring to Xie et al. [22 (link),23 (link)]. For the saponified cake samples, we extracted a mixture with n-hexane/ethyl acetate (9:1 v/v) and then collected an organic layer. After evaporation, the residues were dissolved in isopropanol (1%) n-hexane solution for HPLC. Equipped with a Waters 2475Multi λ Fluorescence Detector and Waters 515 HPLC pump, an NP-HPLC system was chosen for vitamin E determination. Additionally, an Agilent ZORBAX RX-SIL column was used. By the comparison of retention time between samples and standards, the identification of vitamin E was carried out. The results were reported as µg/100 g sample (mean ± SD, n = 3).