Rheological properties of cholesterol‐reduced, yolk‐stabilized mayonnaise

Abstract The effects of cholesterol on droplet size distribution and rheological properties of cholesterol‐reduced egg yolk‐stabilized emulsions were determined. Oil‐in‐water emulsions were prepared by using spray‐dried eggs submitted to different levels of cholesterol reduction (14–81 wt% of cholesterol removed). Cholesterol was extracted in a modified Jennings apparatus with subcritical CO 2 (9°C and 4.66·10 6 Pa). Oscillatory and steady flow tests, as well as droplet size distribution measurements, were carried out on the cholesterol‐reduced egg yolk‐stabilized emulsions. The rheological parameters increased with the level of cholesterol reduction up to 40–80 wt% for emulsions having the same total amount of egg yolk. Opposite results, however, were obtined with some emulsions stabilized by a highly cholesterol‐reduced (≈80 wt%) egg yolk. These results were explained by taking into account two opposite phenomena: an increase in the concentration of surface‐active agents as cholesterol content decreased, and a lipoprotein structural rearrangement induced by cholesterol removal.