This is the problem with the refrigeration. I was waiting for someone to
post it and thank you Robik for the excellent assessment of the situation.
Chances are there's absolutely nothing wrong with the counts on the plates.
Organisms that grow at 2-8C probably won't grow fast enough in 24 hours to
over grow anything. So the results are "probably" fine. The problem is
having to use the words probably and fine together in a quality discussion.
The root of the problem is the results are not valid. Unless of course the
method has been validated, which is the real question. Has the practice of
refrigerating and re-incubating been validated?
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Email [log in to unmask]
From: Robik Hartounian [mailto:[log in to unmask]]
Sent: Monday, December 15, 2003 1:31 PM
To: [log in to unmask]
Subject: Re: [PMFLIST] incubation time question???
I believe the results of day 5 (Monday) are invalid since adding extra
stress to the growth conditions on day 4 (Saturday) would have unforeseeable
impact on the organisms present in the sample.
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