title: Fate of mesophilic aerobic bacteria and Salmonella enterica on the surface of eggs as affected by chicken feces, storage temperature, and relative humidity.
abstract: We compared the microbiological quality of chicken eggshells obtained from a traditional wholesale market and a modern supermarket. We also determined the survival and growth characteristics of naturally occurring mesophilic aerobic bacteria (MAB) and artificially inoculated Salmonella enterica on eggshells under various environmental conditions (presence of chicken feces, temperature [4, 12, or 25 °C], and relative humidity [RH; 43 or 85%]). The populations of MAB, coliforms, and molds and yeasts on eggshells purchased from a traditional wholesale market were significantly (P ≤ 0.05) higher than those from a modern supermarket. In the second study, when we stored uninoculated eggs under various storage conditions, the population of MAB on eggshells (4.7-4.9 log CFU/egg) remained constant for 21 days, regardless of storage conditions. However, when eggshells were inoculated with S. enterica and stored under the same conditions, populations of the pathogen decreased significantly (P ≤ 0.05) under all tested conditions. Survival of S. enterica increased significantly (P ≤ 0.05) in the presence of feces, at low temperatures, and at low RH. These observations will be of value when predicting the behavior of microorganisms on eggshells and selecting storage conditions that reduce the populations of S. enterica on eggshells during distribution.
authors: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Anam-dong, Sungbuk-ku, Seoul, 136-701, Republic of Korea.
authors: Sunhyung
authors: S
authors: Park
authors: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Anam-dong, Sungbuk-ku, Seoul, 136-701, Republic of Korea.
authors: Seonyeong
authors: S
authors: Choi
authors: Division of Human Environmental Sciences, Wonkwang University, Shinyong-dong, Iksan, Jeonbuk, 570-749, Republic of Korea.
authors: Hoikyung
authors: H
authors: Kim
authors: Korea Food Research Institute, Baekhyun-dong, Seongnam, Gyeonggi, 463-746, Republic of Korea.
authors: Yoonsook
authors: Y
authors: Kim
authors: Korea Food Research Institute, Baekhyun-dong, Seongnam, Gyeonggi, 463-746, Republic of Korea.
authors: Byeong-sam
authors: BS
authors: Kim
authors: Center for Food Safety and Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, GA, 30223-1797, USA.
authors: Larry R
authors: LR
authors: Beuchat
authors: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Anam-dong, Sungbuk-ku, Seoul, 136-701, Republic of Korea. Electronic address: escheri@korea.ac.kr.
authors: Jee-Hoon
authors: JH
authors: Ryu
mesh_terms: D000818:Animals; D001420:Bacteria, Aerobic / Q000254:growth & development* / Q000302:isolation & purification; D002645:Chickens; D003080:Cold Temperature; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004528:Egg Shell / Q000382:microbiology; D004531:Eggs / Q000382:microbiology*; D005243:Feces / Q000382:microbiology*; D005506:Food Contamination / Q000032:analysis; D061353:Food Storage / Q000295:instrumentation / Q000379:methods*; D006813:Humidity; D019779:Salmonella enterica / Q000254:growth & development* / Q000302:isolation & purification
keywords: Chicken feces; Eggshells; Relative humidity; Salmonella enterica; Temperature