Frogkarma <frogkarma at aol.com> wrote in message
19990624204225.06507.00003683 at ng-fo1.aol.com...
>This is very interesting. Two questions:
>1) Do you think other salts (Sodium Sulfate for instance) would affect the
>growth factors due to the specific salt or is it just a matter of water
>activity?
>>2) What do you mean when you say that the Pathogens have minimal water
>activity?
>>Thanks,
>>Kevin
1) If NaCl affects growth by lowering water activity (and this is what I've
been taught) then any electrolyte should do the trick.
2) Water activity is a good way to express water availability. Salts
dissociate in water and the charged ions attract water molecules. Those
water molecules place themselves in layers round the ions and make
themselves unavailable to bacteria and
fungi. Thus a low water activity indicates less water available for growth
and this is why salted food is conserved.
Kostas
