3D printing of plant-based fat inks towards manufacturing complex cellular agriculture products with fatty structures

3D printing of food is becoming increasingly popular and efforts are being directed at using this technology for cellular agriculture applications. Cell-based food products can be manufactured using 3D bioprinting processes combining different materials to obtain whole-meat structures including muscle, fat, and connective tissue. Therefore, there is a pressing need towards formulating inks that are printable at relatively low temperature levels (<40 °C) and printing pressures (<20 psi) exhibiting good printability and shape fidelity. Different fat-based inks based on sunflower oil (SFO), rapeseed oil (RSO) and olive oil (OO) were developed in this work fulfilling the aforementioned criteria. These inks presented comparable mechanical properties to animal tissues, more specifically to raw salmon fillet. Soy protein isolate (SPI) and κ-carrageenan (κ-CA) were used together with the different vegetable oils as emulsifiers and gelation agents, respectively. Additionally, carnauba wax (Cwax) was also incorporated into the above-mentioned vegetable oils to formulate oleogels (SFOwax). Biocompatibility and cell adhesion assays conducted with embryonic sea bass cells (DLEC, Dicentrarchus labrax Embryonic Cell Line) support their potential use in hybrid structures compatible with bioinks for 3D printing of food. Sensory properties of pure moulded fat-based samples and hybrids (moulded and printed) were evaluated in a double-compression test. In a second step, SFO and SFOwax were enriched with omega-3 oil, to improve their nutraceutical value. Finally, prototypes were developed using SFO40, confirming its great printability and suitability for the 3D printing of large and complex constructs. We present here for the first time a fully vegan, edible and 3D printable ink based on fat emulsions and oleogels compatible with fish cells for the development of 3D bioprinted food products.