Fig. 3. Microbial reduction (log CFU g−1) of Escherichia coli O157:H7 (A), non-O157 Escherichia coli (B), Listeria monocytogenes (C), and Salmonella typhimurium (D) present on ready-to-eat lettuce. The column indicates mean ± standard deviation, and the different letters above the columns indicate significant differences (P < 0.05). PHMG: polyhexamethylene guanidine hydrochloride; PMS: potassium peroxymonosulfate.
