Inactivation of Escherichia coli O157:H7 on raw vegetable sprouts

Abstract

The effect of chlorine wash in combination with calcinated calcium spray on E. coli O157:H7 population reduction on radish sprouts was investigated. The results showed that spraying radish seeds soaked in 200 ppm chlorine solution with 0.04% calcinated calcium solution had potential in inhibiting growth of E. coli O157:H7. The study also demonstrated that 20,000 ppm chlorine wash was not sufficient to completely eliminate E. coli O157:H7 on radish seeds. The effect of seed surface roughness on E. coli O!57:H7 population reduction by selected sanitizers was also studied. Among the seeds tested, radish seed was the roughest followed by broccoli and alfalfa seeds. A combination of 10% malic acid and 1% TDS (a surfactant) seemed to be as or more effective than 20,000 ppm chlorine in inactivating E. coli O157:H7 on alfalfa, broccoli, and radish seeds. In general, there was a negative correlation between seed surface roughness and E. coli O157:H7 population reduction.