Portable Hyperspectral Imaging Device for Surface Sanitation Verification in the Produce Industry

Abstract

Produce processors must clean and sanitize surfaces before production to reduce the risk of foodborne illness. Current surface hygiene verification methods require direct surface sub-sampling at selected locations and a wait time. To augment these methods, a portable hyperspectral imaging device was developed to find potential contaminants in real-time and increase sub-sampling effectiveness. Analysis of hyperspectral fluorescence images showed that fresh-cut produce processing exudates in the regions of 460-540 and 670-680 nm are detectable from background materials, while select cleaning agents are not. The portable single operator imaging system includes a charge coupled device (CCD) camera, tunable optical filter, laptop, light emitting diodes (LED's) for fluorescence excitation, and a touchscreen display. Within a commercial plant, fluorescence imaging identified produce processing residuals following routine cleaning procedures that were not readily visible to the naked eye. These tests demonstrate the system's potential to enhance post-cleaning inspection, and helped improve routine cleaning procedures.