The disinfection effect of nisin and citric acid against Listeria monocytogenes in pure culture and on fresh-cut cucumbers

The disinfection effect of nisin and citric acid separately and in combination at different concentration for inactivation of Listeria monocytogenes ( LM) in pure culture and on fresh- cut cucumbers was investigated. The results showed that both nisin and citric acid possessed considerable disinfection effect against LM in pure culture and on fresh-cut cucumbers, respectively, and the anti-listerial activity increased with the increasing concentration and treatment time.LM in pure culture was under the limit of detection within 5min by 100μg /mL nisin, while it need15min to reduce to that lever on fresh-cut cucumbers.LM was reduce to the lever that under the limit of detection by 0.5% citric acid within 10min in pure culture and within 15min on fresh-cut cucumbers.The anti-listerial activity of the combination of nisin with citric acid was stronger than that of their alone.Combination of 50μg /mL nisin with0.3% citric acid reduced LM to the lever that under the limit of detection in pure culture within 20min and on freshcut cucumbers within 15min. In a conclusion, washing with nisin and citric acid might be applied as an effective preservative to control the growth of Listria monocytogene on fresh-cut cucumbers.