max at gte.net wrote:
>> Yersinia wrote:
>> I think you are talking about Petrifilm, available from 3M. You would
> need to use a liquid sample, about 1 mL. It is not EPA approved if you
> are doing samples for water treatment or for the FDA, I have used the
> film for doing a lot of water sample of our water processing equipment.
> But if it is something that you are testing that is regulated, I wouldn't
> recommend it. It is pretty easy to use. The coliform colonies on the
> endo show up as pink with gas and the total count on aerobic plates show
> up as red colonies.
I worked on this stuff for a while during my stint at 3M. Was validated
for some use in poultry bioburdens in 1986 or so in place of standard
Petri plates. Aavailable are a standard methods-type product with TTC in
it, and a VRB=type plate for coliforms. There are some improvements
coming at some point, not sure what they are or when they'll be
released.
Fred