Solvent-Free Synthesis of High-Purity Sucrose Fatty Acid Monoesters and a Comparison of Their Properties with Those of Their Commercial Counterparts

Most commercially available sucrose esters are prepared using synthetic regimes that require volatile organic compounds as solvents. This results in high manufacturing costs, environmentally deleterious production processes, and products possessing residual toxicities. While solvent-free protocols can address these issues, they often lead to an inadequate monoester content in the final product and thereby lower the market value of the overall product mixture. Accordingly, we now report a practical synthetic protocol that delivers high-purity monostearate sucrose esters under solvent-free conditions. We also describe an effective ultraperformance convergence chromatography-mass spectrometric method for analyzing the synthesized monoesters. Under optimized conditions, the sucrose monoester component of our product mixture is 74.6 wt % and thus comparable to those of the best commercial preparations currently on the market. Evaluation of the emulsifying properties of the solvent-free-derived materials established that, in some cases, these were superior to their commercial counterparts. As such, the solvent-free protocol reported here represents both an economically attractive and environmentally friendly alternative to the potentially polluting sucrose ester production techniques currently employed by industry.