Effect of Nisin and citric acid on the fate of Listeria monocytogenes on fresh-cut crown pears during storage

Sanitizer solution (0.05mg/m L Nisin+0.3% citric acid) and tap water were separately used to wash fresh-cut crown pears inoculated with Listeria monocytogenes (LM) . Washed fresh-cut samples were stored at4, 12 and 24℃ for 5 days to determine the fate of LM during storage, unwashed samples were used as control.The results showed that washing with Nisin combined with citric acid solution significantly reduced the initial level of LM (p <0.05) . LM populations remained relatively unchanged (p >0.05) on sanitizer solution washed fresh-cut samples and small increased on tap water washed and unwashed samples during storage at 4℃.When storage at 12 and 24℃, LM populations significant increased (p<0.05) on the fresh-cut pears. Results indicated that washing with Nisin and citric acid combined with storage at a refrigeration temperature might be applied as an effective preservative for controlling the growth of LM on fresh-cut crown pears.