Inactivation of Enterobacter sakazakii Inoculated on Formulated Infant Foods by Intense Pulsed Light Treatment

  • Choi, Mun-Sil (Department of Food Science and Technology, Ewha Womans University) ;
  • Cheigh, Chan-Ick (Department of Food Science and Technology, Ewha Womans University) ;
  • Jeong, Eun-Ae (Department of Food Science and Technology, Ewha Womans University) ;
  • Shin, Jung-Kue (Department of Korean Traditional Food Culture, Jeonju University) ;
  • Park, Ji-Yong (Department of Biotechnology, Yonsei University) ;
  • Song, Kyung-Bin (Department of Food Science and Technology, Chungnam National University) ;
  • Park, Jong-Hyun (Department of Food Science and Biotechnology, Kyungwon University) ;
  • Kwon, Ki-Sung (Center for Food Safety Evaluation, Korea Food & Drug Administration) ;
  • Chung, Myong-Soo (Department of Food Science and Technology, Ewha Womans University)
  • Published : 2009.12.31


Enterobacter sakazakii is a representative microorganism whose presence in infant foods can cause serious disease. The purposes of this study were to determine the inactivation effects of intense pulsed light (IPL) on E. sakazakii and the commercial feasibility of this sterilization method. The inactivation of E. sakazakii increased with increasing electric power and treatment time. The cells were reduced by 5 log cycles for 4.6 and 1.8 msec of treatment at 10 and 15 kV of electric field strength, respectively. The sterilization effects on commercial infant foods were investigated at 15 kV. The cell population in an infant beverage, an infant meal, and an infant powdered milk product inoculated with E. sakazakii were inactivated exponentially as a function of time and reduced by 4.0, 2.5, and 1.5 log cycles for 9.4, 7.0, and 7.0 msec of treatment time, respectively.


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