Customized 3D printing to build plant-based meats: Spirulina platensis protein-based Pickering emulsion gels as fat analogs

To expand the application of emulsion gels as fat replacers in food systems, they were applied as fat analogs for plant-based meats by single-channel and dual-channel 3D printing. Spirulina platensis protein, as sustainable food sources, exhibits excellent emulsifying ability and has been generated into nanoparticles to stabilize emulsions. Three novel fat analogs: spirulina platensis protein nanoparticle based Pickering emulsions gels (SPP); nanoparticles/xanthan gum-based emulsions gels (SPP-XG); nanoparticles/xanthan gum/sunflower wax-based emulsions gels (Bigel); and three conventional oils: coconut oil; palm oil; and oleogel were regarded as fat components. The fat and protein components blended for printing by single-channel 3D printing, resulting in a new type of plant-based meats with extremely high printing accuracy and exhibiting "print inflation". It exhibited lower hardness, which was conducive to chew compared with control ones. The water mobility was weakened as showed in LF-NMR, meaning the improved water holding capacity of plant-based meats. Protein and oil matrix were loaded into two printing cartridges respectively for dual-channel 3D printing, Bigels and palm oil (PO) served as a comparison of oil types. The cooking loss and shrinkage of Bigel-based plant-based meats obtained by this method were at extremely low level with 4.81% ~ 6.20% and 5.16% ~ 7.72%, respectively. As the oil content increased to 60%, the PO-plant-based meats collapsed and lost their printing structure, while Bigel-plant-based meats exhibited better printing effects, which can be regarded as an ideal special fat for 3D printing to construct plant-based meats.