The filling effects of starch-based emulsion microgels in gel-based systems

The emergence of emulsion microgels, formed from one or more emulsion droplets encapsulated in a soft solid, with mechanical properties that mimic the sensory properties of fat, holds promise for fat replacement applications in gel-based food products. This study builds upon the existing knowledge of emulsions and emulsion gels, focusing on the design and characterization of starch-based emulsion microgels as functional fillers in gel matrices. In brief, emulsions stabilized by octenyl succinic anhydride (OSA)-modified starch was prepared first at an oil mass fraction ratio of 60%. Then, the obtained OSA starch stabilized emulsion was mixed with natural wheat starch at varying ratios to prepare emulsion microgel through a top-down approach. And the particle sizes of these emulsion microgels ranged from 10 to 100 μm, in addition, rheological analysis showed that microgels had solid-like behavior with their storage modulus (G′) exceeding the loss modulus (G″). To evaluate the potential of these emulsion microgels in replacing fats in food systems, the effects of these emulsion microgels as fillers in tapioca starch-based gels was further investigated, with the emulsions serving as filler controls. Microgel-filled gels demonstrated good water-holding capacity and gel strength compared to emulsion-filled gels, indicating their potential to enhance the moisture retention and mechanical properties of food products. Moreover, microgel-filled gels exhibited better deformability resistance and deformation recovery. Overall, emulsion microgels show promise as fillers for improving the sensory and mechanical properties of starch-based gel foods.