How about using a thermometer? It seems pretty simple.
>From: gbmatthew[SMTP:zbc25 at cc.keele.ac.uk]
>Sent: Tuesday, September 10, 1996 7:13 AM
>To: microbio at net.bio.net>Subject: enthalpy of E.coli fermentations
>anyone out there got a simple method for the calculating or estimating
>the heat generated by an aerobic exponentially growing E.coli