Development of a portable hyperspectral imaging system for monitoring the efficacy of sanitation procedures in food processing facilities

Cleaning and sanitation in food processing facilities is a critical step in reducing the risk of transfer of pathogenic organisms to food consumed by the public. Current methods to check the effectiveness of sanitation procedures rely on visual observation and sub-sampling tests such as ATP bioluminescence assays and culturing methods. To augment existing verification methods, a hand-held visible hyperspectral imaging device was developed. The device is capable of acquiring reflectance images using ambient lighting, and fluorescence responses to supplemental violet (405 nm) excitation. To enhance the ability of detecting relatively low intensity fluorescence responses in the presence of ambient lighting, the device includes the ability to identify wavebands where the intensity of ambient lighting is relatively low. Valleys in ambient illumination intensity when using fluorescent lighting were found at around 475, 520, 570, and 675 nm. A principal goal is to acquire data to support development of a commercially-viable, hand-held, imaging system.

► A portable hyperspectral imaging system is described.
► Images at 53 different wavelengths can be acquired in about 11 s.
► System can auto cycle through three selected wavelengths.
► Violet LED excitation allows use of fluorescence-based detection.
► Invisible juice trails from melons could be detected at 675 nm with violet lighting.