One-step rapid extraction of phytosterols from vegetable oils

[Display omitted] •The new phytosterol method was optimized and validated.•The new phytosterol method is easy to carry out.•The new phytosterol method is quick, precise and accurate. The conditions for the extraction of phytosterols (campesterol, stigmasterol and β-sitosterol) from vegetal oils were optimized by means of response surface methodology (RSM). A 24 central composite rotatable design (CCRD) was used to investigate the effects of four independent variables: sample weight (g), saponification temperature (°C), saponification time (h) and number of extractions (n). The CCRD was carried out in 27 trials, including eight axial and three central points; and the response variables were the contents of campesterol, stigmasterol, β-sitosterol and total phytosterols. The optimized conditions established by the RSM were 0.3 g of sample, saponification for 3 h at 50 °C and 4 extractions with n-hexane. Satisfactory values for linearity, recovery, repeatability, accuracy, precision, limits of detection (2.0–2.3 mg/100 g) and quantification (6.5–7.7 mg/100 g) were achieved. The optimized method was also validated by comparison with the official AOCS method, and the contents of stigmasterol and β-sitosterol did not show significant differences (p > 0.05) when determined by both methods. However, low values (p