Use of Fluorogenic Assays for the Enumeration of Escherichia coli from Selected Seafoods

Escherichia coli was enumerated and immediately confirmed by incorporating 4‐methylumbelliferone glucuronide (MUG) into Lactose Broth (LB), Violet Red Bile Agar (VRB) and M‐Endo Broth (M‐Endo) in selected seafoods. E. coli in the seafood samples ranged from 1.0 × 10 1 – 1.0 × 10 3 Most Probable Number (MPN)/g, 1.0 × 10 1 – 3.5 × 10 2 cfu/g and 0.9 × 10 1 – 2.8 × 10 2 cfu/g in LB‐MUG, VRB‐MUG, and M‐Endo‐MUG, respectively. Although not statistically significant (α= 0.05), LB‐MUG resulted in higher counts in fresh finfish, frozen fish and breaded seafoods. Specificity for E. coli in LB‐MUG, VRB‐MUG and M‐Endo MUG was 96.5%, 92.0%, and 90.0%, respectively. All three fluorogenic assays enabled a rapid and sensitive enumeration of E. coli from seafood products.