Comparison of supercritical CO₂ and hexane extraction of lipids from sorghum distillers grains

Abstract

Total yields and compositions of sorghum dried distillers grains with solubles (DDGS) lipids obtained by supercritical CO 2 (SC-CO 2 ) extraction were compared with those obtained by recirculated solvent extraction (RSE) with hexane. The total yield of lipids obtained by SC-CO 2 extraction at 27.5 MPa and 70 7C was 150 g lipids/kg DDGS, while the yield obtained by RSE with hexane at 69 7C was only 85 g lipids/kg DDGS. The contents of four high-value compounds, i.e., policosanols, phytosterols, free fatty acids (FFA) and tocols, in the lipids obtained by SC-CO 2 extraction were 31.2, 15.6, 155.3 and 0.50 mg/g at 27.5 MPa and 70 7C, compared to 26.6, 9.6, 57.3 and 0.03 mg/ g for RSE with hexane at 69 7C. The profiles of phytosterols and FFA in the sorghum DDGS lipids were relatively independent of the extraction methods and operating conditions.

Sugarcane waste as a valuable source of lipophilic molecules

“…Studies have shown that higher concentrations of phytosterol can be extracted with scCO 2 than with soxhlet extractions using DCM or recirculated hexane extraction (Castola et al, 2005;Wang et al, 2007). The triterpenoid profile of the scCO 2 extract was found to be drastically different to that of the hexane soxhlet.…”

Advantages of supercritical fluid extraction for recovery of squalene from wine lees

“…On comparison to the previously reported UAE using hexane for recovery of SQ from wine lees [11] the similarities found in the chemical composition of the obtained lipids is due to comparable hydrophobicity of SCCO 2 and hexane [36]. Yet, SCCO 2 was found to be superior to hexane as no oxidation products were evidenced.…”

Sorghum Fermentation for Nutritional Improvement

“…Sorghum grains are a relatively rich source of phytosterols when compared with fruits, vegetables, and other cereal grains commonly found in the food supply. Presently more than 200 sterols reported in vegetables, 3 have been identified in sorghum (sitosterol: 44.8 to 48.2%; campesterol: 26.1 to 38.0% and stigmasterol: 17.3% to 25.6%) (Wang et al 2007; Ye et al 2010).…”