My research program is focused on the safety and microbial ecology of fermented and acidified vegetable products. The tools we used for these studies include: from high-throughput DNA sequencing and bioinformatics, measurements of internal cell pH and metabolites in bacteria undergoing acid stress, and mathematical models for buffering, pH and the growth and death of microorganisms acidic foods. A common theme in my research is the study of microbial competition. Applications include determining conditions that assure pathogens are killed during commercial processing of fermented and acidified vegetables, and how probiotic lactic acid bacterial cultures can survive in these foods.