Freezing and salmonella?

Enigl enigl at
Wed Aug 13 08:45:07 EST 1997

In article <5sofk1$7j4$1 at>, "J. McGrath"
<jmcg at> writes:

>   Microorganisms are often stored (with some preparation) in liquid
>nitrogen (which is at least 200 degrees F below zero) for months to
>years!  Unless their is a "cold sensitive" strain I doubt that this is

There can be a "freeze-reduction" of some coliform bacteria
(_Enterobacter_) developed for some--not all--diary products by my
university.  The conditions are -20F but only a one log reduction in 30
days i.e., D-value = 30 days at -20.  However, to my knowledge,
_Salmonella_ is not validated for this procedure in any product.

Davin C. Enigl, MS-MEAS
(Master of Science=Master of Environmental Arts and Sciences)
Sole Proprietorship,  President-Microbiologist
Quality Assurance, Quality Control, Research and Development

Co-author of _Preservative-Free and Self-Preserving Cosmetics and Drugs_,
Kabara and Orth, eds.
Copyright 1997, Marcel-Dekker, ISBN 0-8247-9366-8

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August 12, 1997
8:53 pm PACIFIC

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