Virginia Tech
Use of Ultraviolet Light for the Inactivation of Listeria monocytogenes and Lactic Acid Bacteria Species in Recycled Chill Brines
Abstract
dc:description.abstractReady-to-eat meat products have been implicated in several foodborne listeriosis outbreaks. Microbial contamination of these products can occur after the product has been thermally processed and is being rapidly chilled using salt brines. The objective of this study was to determine the effect of ultraviolet irradiation on the inactivation of Listeria monocytogenes and lactic acid bacteria in a model brine chiller system. Two concentrations of brines (7.9%w/w or 13.2%w/w) were inoculated with a ~6.0 log10 CFU/ml cocktail of L. monocytogenes or lactic acid bacteria and passed through the ultraviolet (UV) treatment system for 60 minutes. Three replications of each bacteria and brine combination were performed and resulted in at least a 4.5 log reduction in microbial numbers in all treated brines after exposure to ultraviolet light. Bacterial populations were significantly reduced after five minutes exposure to UV light in the model brine chiller as compared to the control, which received no UV light exposure (P<0.05). The maximum rate of inactivation for both microorganisms in treated brines occurred between minute 1 and 15 of ultraviolet exposure. Overall, results indicate that inline treatment of chill brines with ultraviolet light (UVC) shows promise in inactivating L. monocytogenes and lactic acid bacteria. Due to the low capital involved in initiating a continuous inline UV system, the use of ultraviolet energy may prove to be beneficial for effectively controlling pathogens in recycled chill brines without interrupting the chilling operation. An inline ultraviolet system could be used in a hazard analysis and critical control points plan.
Degree
thesis:*- Name thesis:degree_name
- Master of Science
- Level thesis:degree_level
- masters
- Discipline thesis:degree_discipline
- Food Science and Technology
- Department dc:contributor.department
- Food Science and Technology
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 2003
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Gailunas, Karol Marie
- Chair dc:contributor.committeechair
-
- Sumner, Susan S.
- Committee members dc:contributor.committeemember
-
- Williams, Robert C.
- Alvarado, Christine Z.
Subjects
dc:subject × 4Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
Identifiers
dc:identifier.*- Dc Identifier Other
- etd-07092003-140629
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/33938