Effects of ϵ-polylysine and milk serum protein on the attachment and decontamination of Salmonella Enteritidis on lettuce and radish sprouts

To understand the effects of pretreatment of lettuce during cultivation with 0.001% '-polylysine (PL) in combination with 0.25% milk serum protein (MSP) on the attachment of Salmonella Enteritidis, lettuce leaves were contaminated with S. Enteritidis after a 1-day treatment with food additives, and harvested after cultivation for 1 day. Viable S. Enteritidis counts on lettuce leaves pretreated with the PL and MSP mixture were significantly reduced from 5.7 log CFU/g to 1 log CFU/g after decontamination by washing with water and a subsequent treatment with NaClO. The viable S. Enteritidis counts on radish sprouts grown for 7 d in the presence of 0.01% PL from seeds inoculated with S. Enteritidis were reduced to 3.1 log CFU/50 sprouts after NaClO decontamination. These counts were significantly lower (P < 0.05) than those of plants without additive(s). The treatment with additive(s) did not affect the ascorbic acid and chlorophyll contents of both plants.