Ercili Cura et al. investigated the effects of a novel tyrosinase from Trichoderma reesei in structure modification of chemically acidified sodium caseinate and skim milk gels. Enzyme-aided structure engineering of dairy products has taken much interest since the introduction of transglutaminase (TG), a transferase capable of forming inter- or intramolecular isopeptide bonds in protein systems. TG-aided crosslinking of caseins has been reported to lead to milk protein gels with increased firmness and less syneresis. Tyrosinase is an interesting alternative to TG, due to its different mode of action. In the presence of oxygen, tyrosinase is capable of oxidizing tyrosine residues in protein molecules, resulting in the formation of protein-protein crosslinking.