Comparing extraction buffers to identify optimal method to extract somatic coliphages from sewage sludges

► Somatic coliphages can be used as process indicators of sewage treatment efficacy. ► Efficient methods to extract coliphages from sewage sludges for enumeration are lacking. ► Twelve different extraction procedures were compared. ► Highest recovery was 16% using 10% beef extract at pH 9.0. ► Additional research is needed to develop better coliphage extraction methods.