Effect of Formic and Propionic Acid Mixture on Escherichia Coli in Fish Meal Stored at 12^oC

Adam Malicki, Wojciech Zawadzki, Szymon Bruzewicz, Stanislaw Graczyk and Albert Czerski

The purpose of paper was the evaluation of short-chain organic acid effect on Escherichia coli in fish meal stored at 12^oC. Fish meal samples (n=125) were inoculated with 7 x 10⁷ CFU x g^-1 of E. coli ATCC 25922 strain and treated with 0 to 1.2% of formic (35%) and propionic (15%) acid mixture. The treatment resulted in the significant reduction of number of test bacteria, proportional to the concentration of acid added. When applied in mixture, propionic and formic acid appeared to work synergistically against E. coli. Accordingly, their application as high-protein feed preservatives seems to be highly appropriate.