ARS | Publication request: FLUORESCENT DETECTION OF FECAL CONTAMINATION ON ANIMAL CARCASSES (ORAL PRESENTATION)

Submitted to: Conference on Gastrointestinal Function
Publication Type: Abstract Only
Publication Acceptance Date: March 12, 2003
Publication Date: March 12, 2003
Citation: RASMUSSEN, M.A., CASEY, T.A., PETRICH, J.W. FLUORESCENT DETECTION OF FECAL CONTAMINATION ON ANIMAL CARCASSES. CONFERENCE ON GASTROINTESTINAL FUNCTION. 2003. ABSTRACT P. 21.

Technical Abstract: Contamination of animal carcasses with feces is an important source of foodborne pathogens such as E. coli.O157:H7. Meat processors require devices that can be used to determine the general level of carcass cleanliness. Current methods include unaided visual inspection of carcasses. However, it is difficult to thoroughly inspect carcasses visually given the rapid chain speeds used in modern meat processing. Improved methods or devices need to be automated for rapid data collection and real time analysis. Such devices should be capable of monitoring slaughter process interventions. Fluorescence spectroscopy has been previously applied to the detection of some contaminants on foods. Several fluorescent markers, which may be useful for the detection of feces, are known including the methanogenic cofactor F420. However, the degradation of green plants in the G.I. tract produces chlorophyll metabolites that are highly fluorescent and more useful markers for a fecal detection system. These metabolites have peak excitation and emission bands near 420 nm and 675 nm, respectively, and meat contributes little background fluorescence at these wavelengths. Chlorophyll metabolites are commonly present in the G.I. tract of herbivorous animals. We have exploited the fluorescent properties of these metabolites for the development of instruments, which can detect fecal contamination on meat carcasses in real time. Although diet influences the fluorescent signal, instruments have been designed with sufficient sensitivity for detection of feces from animals consuming commercial finishing diets. These instruments can augment other more time-consuming microbiological testing methods and can assist meat inspectors in their efforts to minimize contamination on meat.