Total antioxidant capacity (TAC) is a global measure of the non-enzymatic antioxidant activity that integrates the individual effect of all antioxidants in a given matrix, and their additive, synergistic or antagonistic interactions. TAC is considered as an important parameter to establish the redox state of agri-food samples.

Due to the transient nature of ROS/RNS, their measurement in agri-food samples is very difficult and the antioxidant capacity or the formation of oxidation products are also usually measured as  markers of the redox state of agri-food products.