NaCl effects on bacterial growth

[MG]

NaCl inhibit growth because it reduce water activity of product. Here after, I give you correspondance between various NaCl solutions and water activity

Percent NaCl  Water activity
  0.9           0.995
  1.7           0.99
  3.5           0.98
  7.0           0.96
 10.0           0.94
 13.0           0.92
 16.0           0.90
 22.0           0.86

Minimum water activity requires for bacterial growth varies as a function of strains.

Pathogen                       Minimal water activity
Campylobacter jejuni                0.990
Aeromonas hydrophila                0.970
Clostridium botulinum E             0.965
Clostridium botulinum G             0.965
Shigella spp.                       0.960
Yersinia enterocolitica             0.960
Clostridium perfringens             0.945
Clostridium botulinum A et B        0.940
Salmonella spp.                     0.940
Escherichia coli                    0.935
Vibrio parahaemolyticus             0.936
Bacillus cereus                     0.930
Listeria monocytogenes              0.920
Staphylococcus aureus (anaerobic)   0.910
Staphylococcus aureus (aerobic)     0.860

You can find a lot of interesting informations in the article :
CHIRIFE J. and Del PILARBUERA M. (1996) Water activity, water glass dynamics, and the control
of microbiological growth in foods. Critical reviews in Food Science and Nutrition, 36 (5),
465-513

Yours sincerely,





Marielle Gay

ASEPT
Tél.: 33 2 43 49 22 22 - Fax : 33 2 43 53 36 53
E-mail : m.gay at asept.asso.fr
http://www.asept.asso.fr


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