Incidence of Nitrite-Depleting Lactic Acid Bacteria in Cured Meats and in Meat Starter Cultures

Abstract

Lactic acid bacteria were isolated from commercial packages of chicken loaf, bologna, Thuringer sausage and summer sausage. The bacteria were identified. The ability of these isolates to deplete nitrite was assessed during growth studies in broth cultures. The Lactobacillus plantarum components of four commercial meat starter cultures were also studied. All of the starter cultures and 68% of the isolates caused 59 to 93% depletion of 200 μg of nitrite per ml of APT broth over 24 h at 30°C. Two mechanisms of nitrite depletion were observed: chemical depletion due to acid production during growth, and enzymatic depletion. To assess enzymatic depletion of nitrite, the pH was maintained at 6.2. Six isolates were found to deplete nitrite up to 100% within 24 h at 22°C due to enzymatic activity. The starter cultures possessed weak enzyme activity, depleting nitrite by 10 to 28% over 24 h.