1,3-diglyceride-rich edible oils from glycerolysis of vegetable oils: Effect of the catalyst basic properties

Abstract

Vegetable edible oils enriched in diglycerides were obtained by glycerolysis under heterogeneous catalysis conditions using MgO as catalyst. These oils contain up to 32% of the 1,3-diglyceride isomer, which is believed to present unique nutritional properties to prevent obesity, compared to triglycerides or 1,2-diglycerides. The base site density and strength distribution of the different sites (weak, medium and strong) present on MgO as well as the initial oil conversion rate depend on the preparation procedure. The density of medium-strength sites increases upon increasing the severity of the preparation procedure in the range of 673-873K in parallel to the initial oil conversion rate. These results confirm that medium-strength base sites promote the kinetically relevant reaction steps involved in the glycerolysis of vegetable oils.