Oxidized form of vitamin C, which together with ascorbic acid (the reduced form), makes up the total vitamin C activity in a substance. Present in many food materials, where it has been implicated in browning or discoloration reactions in certain matrices, such as citrus juices. In breadmaking, dehydroascorbic acid is formed from ascorbic acid (used in bakery additives) and acts as an oxidizing agent, promoting formation of disulfide bonds (important for dough strength).