• English
    • Welsh
  • English 
    • English
    • Welsh
  • Login
Search DSpace:
  • Home
  • Research at Cardiff Met
  • Library Services
  • Contact Us
View item 
  • DSpace home
  • Theses
  • PhD theses \ Traethodau PhD
  • View item
  • DSpace home
  • Theses
  • PhD theses \ Traethodau PhD
  • View item
JavaScript is disabled for your browser. Some features of this site may not work without it.

The effect of ozone and open air factor on environmental microbial isolates of significance in the food industry

Thumbnail
View/open
Thesis version 4 ( 18-04-2014) FINAL VERSION.pdf (17.15Mb)
Author
Nicholas, Rebecca Charlotte
Date
2014
Type
Thesis
Publisher
Cardiff Metropolitan University
Metadata
Show full item record
Abstract
Ozone and open air factor (OAF) have been reported in the research literature as being effective anti-microbial agents. The action of ozone on microbes is relatively well understood, but the action of OAF is not well characterised. Both ozone and OAF have relatively short half-lives and do not leave behind toxic residues. The advantages of using a gas instead of aerosols, or droplets produced by fogging to decontaminate surfaces, is that a gas will come into contact with the horizontal, vertical and inverted planes of the surfaces (by diffusion), whereas aerosols or droplets will be affected by gravity. The effect of gaseous ozone, OAF and ozonated water with or without d-limonene emulsified in alcohol on surface attached and biofilm environmental L. monocytogenes amd P. aeruginosa were investigated. The interaction of each treatment with microorganisms was elucidated by determining microbial survival on different food contact surfaces, detecting cell injury by examining treated environmental L. monocytogenes cells using scanning electron and atomic force microscopy. All treatments were significantly more effective in eliminating the gram negative than the gram positive bacteria. This may be due to differences in cell wall structure and the cell’s ability to produce extracellular polymeric substances. Scanning electron microscopy revealed that gaseous ozone caused the cells to bleb out their cellular contents, whereas for OAF treated cells, holes were apparent in the cell wall. The ozonated water treatments were more effective in stripping the biofilm away from the surface substrata. The atomic force microscope showed that OAF, ozonated water and terpene, and the terpene in water treatments caused visible cell surface property changes, compared to gaseous ozone and ozonated water treatment alone.
URI
http://hdl.handle.net/10369/7557
Description
PhD Thesis
Collections
  • PhD theses \ Traethodau PhD [469]

Related items

Showing items related by title, author, subject and abstract.

  • Thumbnail

    A COMPARISON OF THE PHYSIOLOGICAL EFFECTS OF DIFFERENT PLAYING SURFACES ON WATER-BASED AND SAND-BASED TURF WITH SPECIAL REFERENCE TO FATIGUE 

    Lomax, Lucy (Cardiff Metropolitan University, 2013)
    This study is the first to compare the physiological effects of different types of artificial turfs used in field hockey with special reference to fatigue. In football, there have been previous ambiguous results on the ...
  • Thumbnail

    What effect do different feet positions have on backstroke start 

    Gosling, Declan (Cardiff Metropolitan University, 2013)
    The purpose of this study was to determine the effect that different feet positions have on backstroke start effectiveness. The aims of this study were to discover how effective four different backstroke starts were. The ...
  • Thumbnail

    A study to assess alternative water sources for reducing energy consumption in a medical facility case study, Abu Dhabi 

    Seguela, Geraldine; Littlewood, John; Karani, George (Elsevier, 2017-10-23)
    This paper presents the case for water and energy conservation in a desert type climate healthcare environment, which is based on the need for Abu Dhabi to decrease potable water and energy consumption to reduce environmental ...

Browse

DSpace at Cardiff MetCommunities & CollectionsBy issue dateAuthorsTitlesSubjectsThis collectionBy issue dateAuthorsTitlesSubjects

My Account

Login

Statistics

Most Popular ItemsStatistics by CountryMost Popular Authors

DSpace software copyright © 2002-2015  DuraSpace
Contact us | Send feedback | Administrator