Journal of Food, Agriculture and Environment

Effect of high-pressure treatment on survival of Escherichia coli O157:H7 population in tomato juice

Author(s):

Md. Latiful Bari ^1*, Dike O. Ukuku ², Mayuka Mori ³, Shinichi Kawamoto ¹, Kazutaka Yamamoto ¹

Recieved Date: 2006-09-13, Accepted Date: 2006-11-27

Abstract:

Liquid foods have been implicated in numerous food-borne outbreaks and recalls. Tomato juice and phosphate buffer saline inoculated with Escherichia coli O157:H7 at 10⁸ cfu/ml was exposed to continuous or repeated cycles of high-pressure (300 to 600 MPa) treatment at 25°C. Treatments using moderate pressure at 300, 350 and 400 MPa for up to 60 min reduced the population of inoculated E. coli O157:H7 by approximately 3.0, 3.0 and 5.0 log cycles, respectively in tomato juice. Population of E. coli O157:H7 in all samples tested was decreased when temperature was increased from 30 to 40°C. However, increase in temperature and a 600 MPa pressure resulted in more sub-lethal injury on cells inoculated in phosphate buffer than tomato juice. It appeared that the acidity of the tomato juice killed and prevented recovery of the injured bacteria. Repeating the pressure 4 times at 300 MPa for a total of 40 min at room temperature was significant (p<0.05) in reducing E. coli population by extra 1.0 log. The results of this study suggest that repeating high-pressure treatment at least 4 times at 300 MPa for a total of 40 min would inactivate more E. coli O157:H7 strains in tomato juice than using continuous pressure for the same amount of time.

Keywords:

High-hydrostatic pressure, repeating high pressure, Escherichia coli O157:H7, phosphate buffer, tomato juice

---

Journal: Journal of Food, Agriculture and Environment
Year: 2007
Volume: 5
Issue: 1
Category: Food and Health
Pages: 111-115

---

Full text for Subscribers

---

Information:

Note to users

The requested document is freely available only to subscribers/registered users with an online subscription to the Journal of Food, Agriculture & Environment. If you have set up a personal subscription to this title please enter your user name and password. All abstracts are available for free.

Article purchasing

If you like to purchase this specific document such as article, review or this journal issue, contact us. Specify the title of the article or review, issue, number, volume and date of the publication. Software and compilation, Science & Technology, all rights reserved. Your use of this website details or service is governed by terms of use. Authors are invited to check from time to time news or information.

---

Purchase this Article:   20 Purchase PDF Order Reprints for 15

---

Share this article :