Influencing factors on the ability to assemble a complex meat analogue using a soy-protein-binder

Existing complex meat analogues such as bacon often do not resemble meat-based ones in appearance, texture and techno-functionality. This has been due to them being only composed of a differently colored homogeneous protein matrix, but lack in presence of a fat phase which contributes to frying performance and taste perception. We hypothesized that extruded plant proteins and plant-based fat mimetics can be assembled into a performance-enhanced bacon analogue by using a suitable binder system based on soy protein isolate (SPI), where, furthermore, adhesion can be improved by increasing gel strength. The results showed that extrudates and fat mimetics could not be adhered sufficiently by a heat-induced 14% (w/w) SPI-gel as binder, independent of the applied quantity. Successful adhesion was only achieved when transglutaminase was added to the binding suspension, and only the hardest, transglutaminase cross-linked gels resulted in acceptable cohesion. Overall, our results showed, that gels needed to be formed via covalent, isopeptide bonds to act as functional binders in a bacon analogue whereas gels formed via physical bonds were insufficiently adhesive to function as a binder.