A strange topic for study, we think, but very helpful discovery nonetheless! No more turning up our noses at the crusty bits –
Although previous studies have suggested that bread contains compounds that have a cancer-fighting potential, much focus has been placed on its abundance of dietary fiber, which is believed by some to help prevent colon cancer. The current study is the first to identify a cancer-fighting compound that is concentrated in the crust, says Thomas Hofmann, Ph.D., lead researcher for the study and formerly with the German Research Center of Food Chemistry in Garching, Germany. He is currently a full professor at the University of Munster, Germany.
Using a conventional sourdough mixture containing rye and wheat flour, Hofmann and his associates analyzed bread crust, bread crumbs (the pale softer part of the bread) and flour for antioxidant content and activity. They found that the process of baking bread produced a novel type of antioxidant, called pronyl-lysine, that was eight times more abundant in the crust than in the crumb. The compound was not present in the original flour.
Using human intestinal cells, Hofmann’s collaborator Veronika Faist, Ph.D., a researcher at the Institute of Human Nutrition and Food Science in Kiel, Germany, showed that this crust-derived antioxidant is the most effective component in bread for boosting the level of phase II enzymes, which have been shown in previous studies to play a role in cancer prevention.