Bigels are a new technology with great potential for applications like protection and delivery of bioactive components. Their success with drug delivery in the pharmaceutical industry suggests they may be able to deliver sensitive food compounds. The purpose of this study was to develop and characterize a novel, edible bigel system. The bigel was prepared by homogenizing an oleogel emulsion composed of soy lecithin, stearic acid, soybean oil, and water (two usage levels), and a hydrogel composed of whey protein concentrate (two usage levels) and water. Five ratios of oleogel emulsion:hydrogel were examined and characterization was conducted through small angle x-ray scattering, rheology, and fluorescence microscopy. With addition of the hydrogel component, the oleogel emulsion retained its basic structural characteristics, but lost higher order structuring. The bigels were found to have temperature-dependent G’ values, but from 8 to 98°C the bigel’s showed G’>G’’. Fluorescence microscopy revealed a bi-continuous bigel at equal proportions of oleogel emulsion and hydrogel; nevertheless, when either of those phases increased, one became the dominant continuous phase. Hydrogel addition increased the LVR’s length compared to the pure oleogel emulsion, suggesting an improvement of the gel’s mechanical properties. G’ was greatest at 10 wt% water and 15 wt% protein in the oleogel emulsion and hydrogel, respectively, suggesting a synergy between phases. At protein and water contents outside the aforementioned, the relationship between phases became antagonistic towards the bigel’s mechanical properties. In conclusion, a novel edible bigel was successfully developed with optimal properties for application in foods.
