Design of Aerated Oleogel–Hydrogel Mixtures for 3D Printing of Personalized Cannabis Edibles

Abstract

Cannabis seed oil oleogel structured with Glycerol Monostearate (20% w/w) was mixed with xanthan gum hydrogel (2% w/w) at different ratios ranging from 0% w/w hydrogel to 75% w/w hydrogel, using a syringe-to-syringe apparatus, for the preparation of 3D-printable food inks. This process enabled the simultaneous blend of oleogel and hydrogel phases and the incorporation of air in a reproducible and accurate manner. The printability of bigel inks with different mass ratios was evaluated by using a conventional benchtop food 3D printer. The printability of the inks was found to be negatively affected by the presence of higher portions of the hydrogel phase, while the printing performance of pure cannabis seed oil oleogel was superior compared to the printing performance of the bigel inks. The physicochemical properties of hybrid gels were investigated with rheological studies, thermophysical studies (Differential Scanning Calorimetry), Polarized Light Microscopy, and Confocal Laser Scanning Microscopy. The microstructure of the aerated inks was affected by the presence of a higher oleogel fraction, in terms of air bubble shape and distribution. The addition of hydrogel at concentrations higher than 50% w/w had a strong negative effect on the mechanical properties of the inks leading to a partial collapse of the printed structures and subsequently to poor printing performance.