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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Environmental Microbial & Food Safety Laboratory » Research » Publications at this Location » Publication #309705

Title: Using hyperspectral fluorescence spectra of deli commodities to select wavelengths for surveying deli food contact surfaces

item Lefcourt, Alan
item BECK, ELIZABETH - University Of Maryland
item LO, Y. MARTIN - University Of Maryland
item Kim, Moon

Submitted to: Journal of Biosystems Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/29/2015
Publication Date: 6/1/2015
Citation: Lefcourt, A.M., Beck, E., Lo, Y., Kim, M.S. 2015. Using hyperspectral fluorescence spectra of deli commodities to select wavelengths for surveying deli food contact surfaces. Journal of Biosystems Engineering. 40(2):145-152.

Interpretive Summary: Freshly sliced meats from delis are the number one cause of listerosis in the USA, causing 167 deaths per year and numerous less severe illnesses. Problems with cleaning and sanitation in delis is thought to be a major risk factor for listerosis. This study examines the possibility of using fluorescence imaging to help enhance cleaning efforts in delis. More specifically, this study examines whether common deli commodities such a meats and cheeses might be detected using fluorescence responses to excitation with violet light. Results show that monitoring responses at three wavelengths, 475, 520, and 675 nm, will allow detection of all tested deli commodities. Detection of commodity residues during cleaning will allow more thorough cleaning of deli equipment; particularly in cases where the residues are not easily visible to the naked eye. These results will be of interest to the food industry and scientist working in the area of food safety. If the technology is successfully implemented, the risk of foodborne illness in the general population will be significantly reduced.

Technical Abstract: Problems with assessing the efficacy of cleaning and sanitation procedures in delicatessen departments is a recognized food safety concern. Our laboratory demonstrated that cleaning procedures in produce processing plants can be enhanced using a portable fluorescence imaging device. To explore the feasibility of using fluorescence imaging to detect deli residues, spectra of American, Cheddar, Provolone, and Swiss cheeses and of processed chicken, ham, roast beef, and turkey were acquired using a laboratory hyperspectral imaging system. Commodities were placed on both stainless steel and high density polyethylene coupons. Analysis of hyperspectral fluorescence images showed that cheeses exhibited peaks in the blue-green region and at around 675 nm. Meats exhibited peaks in the blue-green region with one of four ham and one of four chicken brands exhibiting peaks at around 675 nm, presumably due to use of plant-derived additives. When commodities were intermittently imaged over two weeks, locations of spectral peaks were preserved while intensity of peaks at shorter wavelengths increased with time. These results demonstrate that fluorescence imaging techniques have the potential to enhance surface hygiene inspection in deli departments.