Survival of Five Strains of Shiga Toxigenic Escherichia coli in a Sausage Fermentation Model and Subsequent Sensitivity to Stress from Gastric Acid and Intestinal Fluid

Figure 1

Flow chart illustrating the experimental setup. TFS (tube fermented sausage) and control batter (15 g) were transferred to separate stomacher bags, diluted 1 : 10 in gastric acid solution, and stomached for 1 min. Samples were transferred to tubes and incubated for 1, 30, and 120 min (samples G1, G30, and G120, resp.). Furthermore, intestinal fluid solution was added to samples after 30 and 120 min (1 : 1). Sampling from G30 and G120 tubes was performed after 30, 120, and 240 min. Each experiment was repeated three times and included 2 sample types (fermented and controls) × 2 parallels × 5 E. coli strains. A total of 60 (3 × 20) samples were included for the digestion challenge study.