Sample extraction for E. coli testing (IMAGE) Purdue University Caption Kal Holder, undergraduate student in biological sciences, extracts a sample of beef mixed with an enrichment that will speed up the process of determining if pathogenic E. coli is present. Credit Purdue Agricultural Communications photo/Tom Campbell Usage Restrictions This image may be used by news organizations in reports referencing Purdue University’s E. coli assay for rapid testing of raw beef. License Original 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.