Title: Survival, injury and inactivation of human bacterial pathogens in foods: effect of thermal and non-thermal treatments Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: October 24, 2010
Publication Date: N/A
Technical Abstract: Contamination of fruit surfaces and juices with human bacterial pathogens and the pathogens’ ability to survive in low acid fruit juices has caused numerous illnesses and some fatalities. For example, from 1923 to 2000, consumption of contaminated fruit juices has been implicated in at least 28 foodborne illness outbreaks. Eleven out of 28 (almost 40%) outbreaks were associated with Salmonella spp. Eight out of 28 (close to 30%) outbreaks were caused by enteropathogenic Escherichia coli especially E. coli O157:H7. All these outbreaks involving E. coli O157:H7 and Salmonella have raised concerns about the safety of consuming unpasteurized fruit juices. Physical and chemical treatments are used in food processing to eliminate or at least reduce the presence of human bacterial pathogens and spoilage microorganisms in foods. Thermal processing is mostly used by the juice industry to inactivate food borne pathogens in foods however; it impairs the characteristic flavor of juices. People are becoming more health conscious and tend to opt for less heat processed foods. Therefore, there is a need for alternative processing treatments that can achieve a 5 log reduction of bacterial pathogens without causing adverse effect on the flavor of the juice. Several non-thermal technologies for food processing have been proposed, developed and commercialized. Among these technologies are; Pulsed Electric Fields (PEF), Radio Frequency Electric Fields (RFEF), UV and Pulse light, High Hydrostatic Pressure, Thermal Death Time (TDT) devices and GRAS antimicrobial compounds. This presentation will discuss the effect of thermal and non-thermal treatment on viability loss, injury and inactivation of bacterial cells in foods. Also, the effect of storage temperature on the recovery of injured cells will be presented.