Zn, Cu, and Fe Concentrations in Dehydrated Herbs (Thyme, Rosemary, Cloves, Oregano, and Basil) and the Correlation with the Microbial Counts of <i>Listeria monocytogenes</i> and Other Foodborne Pathogens

Abstract

Zn, Cu, and Fe concentrations were measured in dehydrated herbs (thyme, rosemary, cloves, oregano, and basil) marketed in bulk or packaged in glass or polyethylene terephthalate (PET). Microbial counts of Listeria monocytogenes and other five foodborne pathogens were also checked when herbs were previously added to the growing media. The highest mean concentrations were found in basil for Zn and Cu, and in thyme and basil for Fe; the lowest ones for these minerals were in cloves (p p L. monocytogenes, Clostridium perfringens, and Bacillus cereus; they therefore could be used as a natural preservative in food. Aromatic herbs marketed in bulk showed a significantly higher microbial count (p L. monocytogenes, C. perfringens, B. cereus, and psychrophilic microorganisms (p < 0.05), so they could act as a growing factor for the foodborne pathogens.

Keywords

• Zn, Cu, and Fe concentrations
• dehydrated herbs
• microbial counts for foodborne pathogens