Comparison of Performance for Sugar Esters Prepared by a Green Enzymatic Process and a Commercially Available Product
Ye, R, D. G. Hayes, R. Burton, A. Liu, and Y. Wang.  2015.  American Oil Chemistsí Society 106th Annual Meeting, Orlando, 3-6 May 2015.  (invited)

Abstract:
Sugar esters, important biobased surfactants and emulsifiers for foods, cosmetics, pharmaceuticals, and other applications, are traditionally prepared in high-termperature processes, in the presence of organic solvents, and using a stoichiometric excess of reactant. We have successfully prepared sugar esters using green manufacturing: immobilized enzymes, the absence of solvents, and stoichiometric substrate feeds. Therefore, the green manufacturing approach will potentially yield a product meeting user specifications without the need of downstream purification, and the absence of wastes. In this study, the chemical composition, surface and antimicrobial activity of the enzymatically prepared sugar esters were measured, and compared to a commercially available sugar ester product. Typically, the authors' bioreactor system yields a technical grade product, ~85-90% pure, at the 10-30 gram scale. To achieve a higher purity. the technical grade product underwent further esterification, in a very low water activity environment, achieved by operating the reaction in well-sealed dessicators in the presence of dessicant. The study will compare chemical composition and molecular structure, surface and interfacial tension, emulsification, and antimicrobial activity.