Stainless Steel Surfaces Disinfection with Atomized Hydrogen Peroxide
Samuel Bravo González
To study the effectiveness of atomized hydrogen peroxide on stainless steel surfaces in a laminar flow cabinet prototype against reference microorganisms to evaluate sterility in the pharmaceutical industry, as well as health care and food industry high interest microorganisms.
In order to improve traditional cleaning and disinfection in food processing areas food manufacturers need to consider new complementary techniques. One of the techniques that may help to reduce environmental contamination is whole room disinfection. Atomized hydrogen peroxide characteristics as whole room disinfectant are shown below:
Advantages:
- Ability to reach areas such as cracks in gaskets, walls and ceilings.
- Broad spectrum antimicrobial activity.
- Low toxicity and environmentally friendly as it breaks down into water and oxygen.
Disadvantages:
- Expensive equipment.
- Need to remove personnel from the room.
The studied microorganisms were Bacillus atrophaeus, Geobacillus stearothermophilus, Listeria monocytogenes Scott A, Listeria monocytogenes RO15 and methicillin-resistant Staphylococcus aureus (MRSA).
- Treatment showed to be effective against the studied microorganisms. The resistance order was the next: B. atrophaeus > G. stearothermophilus > MRSA > L. monocytogenes RO15 ≥ L.
monocytogenes Scott A.
- Condensate seemed to be effective along with the gaseous phase.
- Testing in the food industry is necessary to verify the process before implementation.
- Further research on biofilms is also necessary to achieve applicable results.
Initial count (log CFU/coupon + SE)
4D reduction (min)
B. atrophaeus 7,09 ± 0,11 25,65
G. stearothermophilus 6,21 ± 0,14 21,60
L. monocytogenes Scott A 6,95 ± 0,28 4,8
L. monocytogenes RO15 6,42 ± 0,19 5,04
MRSA 6,89 ± 0,22 18,97
Table 1. Inactivation parameters obtained for the disinfection process.
Conclusions
Objectives
Introduction
Methods
Results
Figure 1. Inactivation models identified for the disinfection process.
0 5 10 15 20 25 30 35
0.0 2.0 4.0 6.0 8.0 10.0
Tiempo (minutos)
Supervivencia (log ufc/disco)
0 2 4 6 8
0.0 2.0 4.0 6.0 8.0 10.0
Tiempo (minutos)
Supervivencia (log ufc/disco)
0 10 20 30 40 50
0.0 2.0 4.0 6.0 8.0 10.0
Tiempo (minutos)
Supervivencia (log ufc/disco)
0 2 4 6 8
0.0 2.0 4.0 6.0 8.0 10.0
Tiempo (minutos)
Supervivencia (log ufc/disco)
0 5 10 15 20 25 30
0.0 2.0 4.0 6.0 8.0 10.0
Tiempo (minutos)
Supervivencia (log ufc/disco)
Time (minutes)
Time (minutes) Time (minutes)
Time (minutes) Time (minutes)
Survival(logCFU/coupon)Survival(logCFU/coupon)Survival(logCFU/coupon) Survival(logCFU/coupon)Survival(logCFU/coupon)
B. Atrophaeus (Log-linear) G. stearothermophilus (Weibull)
L. monocytogenes Scott A (Weibull) L. monocytogenes RO15 (Weibull)
MRSA (Weibull)
Final Degree Project - June 2021
References
B. atrophaeus
G. stearothermophilus
L. monocytogenes Scott A
L. monocytogenes RO15
MRSA
Disinfection treatment in a laminar flow cabinet prototype (Telstar’s system, ionHP+)
Inoculated on stainless
steel coupons Incubation and
enumeration
- Geeraerd, A.H., Valdramidis, V.P., Van Impe, J.F., 2005. GInaFiT, a freeware tool to assess non-log-linear microbial survivor curves. Int. J. Food Microbiol. 102. https://doi.org/10.1016/j.ijfoodmicro.2004.11.038
- Møretrø, T., Fanebust, H., Fagerlund, A., Langsrud, S., 2019. Whole room disinfection with hydrogen peroxide mist to control Listeria monocytogenes in food industry related environments. Int. J. Food Microbiol. 292, 118-125. https://doi.org/10.1016/j.ijfoodmicro.2018.12.015
