Effect of Sodium Salts of Some Organic Acids on the Germination and Thermal Resistance of Genus Bacillus Spores

Abstract

Sodium salts of several organic acids were tested for inhibitory effect on some genus Bacillus species known to cause spoilage in commercial canned food. It was found that sodium citrate in glucose broth significantly inhibited the germination of B. stearothermophilus and B. coagulans spores, and slightly inhibited that of B. subtilis spores. However, none of the test compounds was effective on B. licheniformis spores.Furthermore, it was shown that addition of sodium citrate to the nutrient broth decreased the thermal resistance of B. stearothermophilus spores. In order to investigate the cause of the inhibition of germination and the decrease of thermal resistance, spores were pretreated with sodium salts of organic acid, and the metals released were analyzed. Large amounts of calcium2+ and magnesium2+ were released from B. stearothermophilus and B. coagulans spores treated with sodium citrate solution. B. licheniformis and B. subtilis spores were unaffected.