Fabrication of ultrastable oil-in-water high internal phase gel emulsions stabilized solely by modified shea butter for 3D structuring

[Display omitted] •High internal phase gel emulsions with jojoba oil were prepared by using shea butter ethoxylates as solely emulsifier.•The HIPGEs showed extraordinary stability and could resist the interference of external conditions.•The HIPGEs exhibited good self-supporting properties during 3D structuring.•The possible mechanism for the high viscosity of HIPGEs compared with previous work are described. High internal phase gel emulsions (HIPGEs) with jojoba oil as internal phase fractions of 83 vol%-92 vol% were prepared by using shea butter ethoxylates (SB-50) of different mass fraction as solely emulsifier. Effects of the internal volume fraction and SB-50 concentration on the formation and stability of oil-in-water HIPGEs were attentively explored by microscope and rheometer, and the mechanism of gel emulsions was proposed. The results indicate that the average particle size of droplets increases with the increase of oil phase volume fraction and emulsifier mass fraction. At the same time, the HIPGEs possess wider linear viscoelastic regions, higher critical stress and higher G', indicating that stronger rheological properties. After heating at 100 °C, all samples were extremely stable. Most of them can maintain good stability after centrifugation, long-time storage or several freeze–thaw treatments. When the mass fraction of SB-50 increases to 3 wt%, the sample shows extraordinary stability and can resist the interference of external conditions such as centrifugation, long-term storage, heating and freezing. The longer carbon chain and wider carbon chain distribution make it possible to form HIPGEs possessing higher viscosity. In the current work, the HIPGEs prepared exhibited good self-supporting properties, which show the possibility to translate the printability and extrudability during 3D structuring. These food-grade HIPGEs can potentially be used as 3D printing inks to make them widely used in cosmetics, food, drug delivery, encapsulation materials, etc.