Superheated water extraction of cholesterol from solid food

A method based on superheated water extraction has been developed for the removal of cholesterol from solid food thus providing a clean approach by avoiding the use of organic solvents. A preconcentration step was also studied with the aim of solving the problem derived from low-cholesterol-content samples and dilution effect. The research also involved the optimisation of the parameters affecting the extraction process by a central composite experimental design as well as a univariate study of the optimisation of the preconcentration step. The time required for total removal of the target compound was 60 min. The method was validated using a certified reference material (NIST-CRM 1845) and was used to analyse food samples within a wide range of cholesterol concentrations. The efficiency for the CRM was 105%. The precision of the method yielded values less than 6.5% (expressed as relative standard deviation) in all instances.