Fabrication and application of starch-based aerogel: Technical strategies

Studies of starch-based aerogels have attracted widespread attention over the last decade, motivated by their environmental friendliness, biodegradability and unique properties. The diversity sources and concentrations of natural starch, the difference in regulation of processing parameters, the employment of gelling improvers or not makes it kind of confusion in fabricating starch-based aerogels for specific uses. This review summarized the fabrication routes of starch-based aerogel, evaluated the internal and external factors modulating the structure and properties, and also described the application progress of starch-based aerogel, mainly focused on food industry. Technical strategies are given for above topics. There are two main fabrication routes of starch-based aerogels based on their shapes: one is for monolith aerogel, another is for microsphere. The parameters including specific surface area, density, pore size, total pore volume, and porosity should be optimized by changing the sources and concentrations of natural starch, the conditions of starch-based hydrogel formation, the methods of solvent removal, and the employment of gelling improvers for different performance requirements. Applications of starch-based aerogels have been extensively explored in food ingredients delivery, food packaging, and thermal isolation. The investigation to date on starch-based aerogel is driven by laboratory-scale fundamental researches, requiring a firmer theoretical foundation and pilot research to narrow the gap between basic research and realistic applications.