How Sour Beer Gets So... Sour (Video) (IMAGE) American Chemical Society Caption Beer samples (right) were collected every 2-3 weeks to track changing concentrations of organic acids and trace components during aging in barrels (left). Credit Bryan Doty/Sour Cellars Usage Restrictions Image may only be used with appropriate credit. 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.