Influence of Modified Atmosphere on Growth of Vegetable Spoilage Bacteria in Media

Six gas mixtures (CO₂/O₂/N₂: 0/5/95, 0/10/90, 5/10/85, 5/20/75, 10/5/85, and 10/20/70) and air were used to investigate the effect of modified atmosphere (MA) on growth of four vegetable spoilage bacteria. In addition, we determined the ability of the MA which most inhibited spoilage bacteria to reduce spoilage in bell peppers inoculated with the respective bacteria. In general, MA did not significantly affect growth of the bacteria tested. Growth of Erwinia , Pseudomonas , Xanthomonas , and Pepper #15 (a pectinolytic Pseudomonas ) at 10 and 20°C was not significantly affected regardless of gas mixtures. At 5°C, growth of Erwinia , Xanthomonas , and Pepper #15 was slightly reduced by some gas mixtures (CO₂/O₂/N₂: 0/5/95, 0/10/90, and 10/5/85; 10/5/85; 0/5/95 and 10/5/85, respectively). Modified atmosphere containing 10% CO₂, 5% O₂, and 85% N₂ did not reduce the ability of bacteria tested to grow at elevated concentrations of sodium chloride. In addition, this MA composition did not change the percentage of bell peppers spoiled by test bacteria inoculated. However, overall visual quality was enhanced by MA.