Transglutaminase modifies the physical stability and digestibility of chickpea protein-stabilized oil-in-water emulsions

This study sought to utilize enzymatic crosslinking to modulate the properties of chickpea-stabilized o/w emulsions and determine its effect on digestibility. Oil-in water emulsions were produced from 40% corn oil and 6% chickpea protein (w/w) with/without addition of transglutaminase (TG). Crosslinking increased the particle size and poly-dispersity, and led to the formation of a gel-like structure (G′ > G″) with 1.5 order of magnitude higher G′ compared to the non-crosslinked emulsion. Enzyme addition improved the emulsion physical stability (over a month) compared to the non-crosslinked emulsion that showed phase separation after two weeks of storage. Results of in vitro digestion showed decreased digestibility of TG-crosslinked chickpea-stabilized emulsions, while proteomic analysis revealed that the crosslinked emulsion is a source of bioactive peptides that are liberated by human digestive enzymes. Overall, application of TG can rationally modify the functionality and digestibility of o/w emulsions towards positive effects on human health.