Bio-oil (image) Cell Press Share Print E-Mail Caption This is a photograph of bio-oil, made of caproic acid and caprylic acid, phase separates out at mildly acidic conditions. Credit Lars Angenent, University of Tübingen Usage Restrictions Credit Required. Share Print E-Mail 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.