The antimicrobial effect of wine on Listeria innocua in a model stomach system

Abstract

A model stomach, containing a food matrix and a synthetic gastric Xuid, was used to study the bactericidal eVect of ingested wine on Listeria innocua. Volumes of wine equivalent to the ingestion of one glass and half a bottle, led, over a period of less than 2 h, to a reduction of 3 and 4 logarithmic cycles of the initial population respectively. The inXuence of ethanol and organic acids, wine constituents with known antimicrobial properties, was investigated. Ethanol exhibited a higher bactericidal eVect than the mixture of the main wine organic acids. When testing the organic acids separately, malic and lactic acids were found to have the strongest eVect. The combination of ethanol with the organic acids acted synergistically but to a lesser extent than wine itself. The results suggest that the ingestion of wine during a meal may diminish the quantity of Listeria persisting further in the alimentary tract.