Optimization of extracting process of waxes from cold-break apple peel by supercritical CO2 and analysis of the composition

The extraction condition of waxes from cold-break apple peel by supercritical CO₂ extraction technology was studied and the composition of apple waxes was analyzed by GC-MS.The optimum condition of supercritical CO₂ were as follows:extraction pressure 35MPa, extraction temperature 50℃, raw material particle size>100 mesh, extraction time 1.5h.Under optimal conditions, the yield of apple waxes was 2.081%.36 compounds of apple waxes were detected.Main ingredients were hydrocarbons and esters which account for 41.44% and 37.41% respectively of all the detected compounds.Alcohols, fatty acids, ketones, β-sitosterol and friedelin were also detected.