Rheological Characterization and Quality of Emulsions Based on Fats Produced during the Reaction Catalyzed by Immobilized Lipase from Rhizomucor Miehei

Abstract

It has been shown that structured lipids, formed in the process of enzymatic modification of natural hard fat with walnut oil, are capable of stabilizing emulsion systems without the need to add additional emulsifiers. This is especially true for emulsions containing fat formed during enzymatic modification when the amount of added water to the reaction catalyst was in the range of 12–16 wt%. Physicochemical evaluations, i.e., the average particle size, its growth, distribution, and dispersity coefficient, were comparable with the reference emulsion where the emulsifier was lecithin, well-known for its emulsifying properties. Microstructure studies also confirmed the above observations. Rheological studies performed on a set of emulsions containing structured lipids of variable composition confirmed that interesterified lipid blends can be directly utilized as a fat base in the preparation of stable emulsions. The consistency, thixotropic behavior, long-term shelf life, and thermal stability of these emulsions were found to be comparable to systems stabilized with conventional emulsifiers, i.e., sunflower lecithine. Our approach offers the opportunity for the preparation of stable emulsion systems, free from additional emulsifiers, for the food or cosmetics industry, which is extremely important from the point of view of the preparation of products free from allergens.