How is TG declared on the label of a final food in EU and why?

Specific labeling is unnecessary from regulatory viewpoint. Different from food additives, there is no technological effect or function of the enzyme in the final product in general. TG in ACTIVA® preparation is not an exception, has no technological effect in the final product due to the fact that the enzyme is inactivated during production process of finished product (mostly by heating) or the substrate of the enzyme has been depleted even if the residues are technologically unavoidable.