Fabrication of aerogel-templated oleogels from alginate-gelatin conjugates for in vitro digestion

In this work, the alginate-gelatin conjugates were developed by Maillard reaction. The aerogel templates were obtained by freeze-drying the conjugates, and they were transformed into oleogels by being immersed in camellia oil. Degree of graft and browning index revealed the occurrence of Maillard reaction. Compared with pure alginate/gelatin samples, the rheology and mechanical properties of mixing samples were improved, indicating the interaction of alginate and gelatin. Aerogel templates formed by Maillard reaction presented the micromorphology of lamellar aggregation, obvious changes of peak intensity in infrared spectrum and better thermal stability. The materials reached a considerable oil adsorption capacity of 23.31 g/g and oil holding capacity of 84.75%. Through Maillard reaction, oleogels showed good in vitro digestion properties. This work suggested that oleogels could be constructed from alginate-gelatin conjugates that formed the aerogel templates for oil adsorption, and Maillard reaction significantly affected the physical structures and oil capacities of alginate-gelatin compound systems.