Investigation of the Emulsifying and In Vitro Digestive Properties of High-Purity Sucrose Monostearate Esters

Long-chain fatty acid mono- and higher-order esters of sucrose are important chemicals, often produced at kilotonne scales, due to their wide range of commercial applications, including as food emulsifiers. While the monoester content of commercial sucrose stearate ester products range up to 75% (in S-1670), this can be further increased to >99% when enzymatic techniques are deployed for product preparation. Although the emulsifying properties of sucrose stearate ester-containing products (such as S-1670) are well-defined, formulations with monoester contents greater than 75% have never been prepared and evaluated. In this study, three sucrose stearate samples with an 80, 85, or 90% monoester content (samples 1–3, respectively) were prepared and the influence of these on their digestive, emulsifying, and rheological properties was studied. The results show that emulsions stabilized by S-1670 (75%) and sample 1 (80%) exhibited the best digestive behavior in a gastrointestinal behavior model, recording 69 and 78% free fatty acid release, respectively. Counterintuitively, an inverted V-shaped profile was observed when the monoester content, which ranged from 75–99%, was plotted as a function of emulsifying properties. These results should serve as an important guide for the development of new sucrose ester products in the food industry.