Growth and Corresponding Elevation of Tomato Juice pH by Bacillus coagulans

B. coagulans was inoculated into sterile, tubed tomato juice and growth and pH were observed for 21 days. Juice samples initially at pH 4.5 supported good growth; pH was elevated to 5.0 after 6 days incubation at 35°C. Other tomato juice samples (initial pH 5.0 or 5.5) also supported good growth of these flat‐sour bacteria and with corresponding increases in pH. The results indicate that flat‐sour spoilage of tomatoes and similar foods may cause decreased acidity, thus possibly allowing outgrowth of Clostridium spores in these water bath‐processed foods.