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The inhibitory effects were investigated of 254-nm ultraviolet (UV) radiation and lactic acid (LA) treatment on populations of Salmonella (S) enteritidis on eggshell surface. All UV exposures (730, 1,580, 3,000 W/cm²) for 30 sec significantly reduced S enteritidis (P 0.05). UV irradiation with 3,000 μW/cm² almost completely eliminated S enteritidis on inoculated eggshells by 99%. These results suggest that the higher intensity of UV irradiation may be associated with the higher germicidal activity. However, no significant differences were detected between UV exposure times. The treatments of LA at the concentration of 0.1, 0.3 and 0.5 % also specifically decreased the bacterial cell populations (0.91 1.14 log CFU) on the eggshell compared with the control (6.92 log CFU). The treatment of LA at the concentration of 0.5 % had the reaction of a 2.52 log unit storage for 9 days. The combined treatment of UV (3,000 μW/cm²) and LA(0.5%) decreased S enteritidis populations on eggshell by 3.85 log unit, compared wth the control (P 0.05), and its inhibitory effect was stronger with storage time.
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