Effects of ε-polylysine and Milk Serum Protein on the Attachment and Decontamination of Salmonella Enteritidis on Lettuce and Radish Sprouts

Abstract

To understand the effects of pretreatment of lettuce during cultivation with 0.001% ε-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.