Effect of NaCl reduction and replacement on the growth of fungi important to the spoilage of bread

Food Microbiol. 2010 Sep;27(6):749-56. doi: 10.1016/j.fm.2010.03.009. Epub 2010 Mar 23.


The effect of NaCl and various NaCl replacers (CaCl(2), MgCl(2), KCl and MgSO(4)) on the growth of Penicillium roqueforti and Aspergillus niger was evaluated at 22 degrees C. In addition, challenge tests were performed on white bread to determine the consequences of NaCl reduction with or without partial replacement on the growth of P. roqueforti. From the results obtained it can be concluded that at equivalent water phase concentrations the isolates exhibited differing sensitivities to the salts evaluated with NaCl and MgCl(2) having the greatest inhibitory action on the growth of A. niger and P. roqueforti, respectively. MgSO(4) had the least antifungal activity. At equivalent molalities, CaCl(2) had in general the largest antifungal activity. Although the water activity (a(w)) lowering effects of the compounds studied play a large role in explaining the trends observed, at equivalent water phase concentrations MgCl(2) was found to have a smaller inhibitory effect on A. niger than that expected from its a(w) depressing effect. The challenge tests revealed that no difference occurred in the growth of P. roqueforti on standard white bread, bread with 30% less NaCl and bread in which 30% of the NaCl has been partially replaced by a mixture of KCl and Sub4Salt. These results are of importance in assessing the possible microbiological consequences of NaCl reduction or replacement in bread and similar bakery products.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aspergillus niger / drug effects*
  • Aspergillus niger / growth & development
  • Bread / microbiology*
  • Calcium Chloride / pharmacology
  • Dose-Response Relationship, Drug
  • Food Microbiology
  • Food Preservation / methods*
  • Food Preservatives / pharmacology*
  • Humans
  • Magnesium Chloride / pharmacology
  • Magnesium Sulfate / pharmacology
  • Penicillium / drug effects*
  • Penicillium / growth & development
  • Potassium Chloride / pharmacology
  • Sodium Chloride / pharmacology*
  • Water / metabolism


  • Food Preservatives
  • Magnesium Chloride
  • Water
  • Sodium Chloride
  • Potassium Chloride
  • Magnesium Sulfate
  • Calcium Chloride