Tailoring oleogel properties from aerogel templates: A comparative study of konjac glucomannan modified by freeze-thaw, ethanol, and alkali strategies.

Abstract

In this study, konjac glucomannan (KGM) hydrogels prepared by freeze-thaw, ethanol, or alkali treatments were converted into aerogel templates via freeze-drying and then adsorbed camellia oil to form oleogels. Scanning electron microscopy showed that alkali-treated KGM aerogels had a compact, uniform porous network with reduced steric hindrance, yielding a superior oil retention capacity. In contrast, aerogels from freeze-thaw and ethanol treatments had a rough mesh structure but a higher oil absorption. Alkali-induced deacetylation partially removed acetyl groups in alkali-treated KGM aerogels, enhancing stability, as verified by Fourier infrared spectroscopy, X-ray diffraction and thermal analysis. Alkali-treated oleogels exhibited remarkable rheological properties, with viscosity recovery reaching 86.81%, reflecting strong structural recovery ability. Notably, alkali-treated KGM aerogels had excellent hardness, chewability and oil retention. This study suggested that oleogels from alkali-treated aerogel templates hold great potential for use in plant-based meat production, offering a novel approach to developing fat substitute materials.