Supercritical CO₂ extraction of egg yolk: Impact of temperature and entrainer on residual protein

Differential scanning calorimetry (DSC) was used to monitor changes in protein conformation resulting from supercritical carbon dioxide (SC‐CO 2 ) extraction of lipids from egg yolk. Extraction temperatures of 65°C and lower had no effect on protein conformation as indicated by similar denaturation temperatures and enthalpies of denaturation (ΔH). An extraction temperature of 75°C resulted in a reduction in the ΔH value for ovalbumin present in the egg yolk. The use of 3% methanol as an entrainer during extraction at 36 MPa and 40°C resulted in a 50% reduction in the ΔH value for ovalbumin. The use of high temperatures and/or entrainers during SC‐CO 2 extraction can result in significant protein denaturation.