The allergenicity of the microbial transglutaminase was evaluated by a medical group at the National University Hospital in Copenhagen, Denmark in 2004 (Pedersen et al., Mol. Nutr. Food Res. 2004: 48(6), 434-440) using the standard FAO/WHO Decision Tree. The researchers concluded that there are no safety concerns with regards to the allergenic potential of microbial TG used in food.