People call it fortification with riboflavin when they add riboflavin to food . The latter organism has been genetically modified to both increase the bacteria 's production of riboflavin and to introduce an antibiotic ( ampicillin ) resistance marker , and is now successfully employed at a commercial scale to produce riboflavin for feed and food fortification purposes . The chemical company BASF has installed a plant in South Korea , which is specialized on riboflavin production using Ashbya gossypii .