Dark Beer has More Iron than Pale Beer (IMAGE) Spanish Foundation for Science and Technology Caption Dark beer contains 121 ppb of free iron compared to 92 ppb in pale beer. Credit SINC Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.