Submitted to: Journal of Food Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/31/2013
Publication Date: 2/8/2013
Citation: Lefcourt, A.M., Wiederoder, M., Kim, M.S., Lo, Y., Liu, N. 2013. Development of a portable hyperspectral imaging system for monitoring the efficacy of sanitation procedures in food processing facilities. Journal of Food Engineering. 117(1):59-66. Interpretive Summary: Cleaning and sanitation is one of the most important measures for reducing the risk of foodborne illness. Currently, the primary means of judging the effectiveness of these measures is visual inspection. Unfortunately, visual inspection has been found to be inadequate, e.g., spot checks of visually-clean surfaces using more sensitive laboratory tests indicate that the surfaces are often still contaminated. To address the need for a better contamination detection method that can provide real-time feedback to users, a portable imagining system was developed. The system incorporates a violet illumination source that can induce fluorescence responses from organic materials, and a tunable optical filter that allows imaging at a selected wavelength, i.e., color. The ability to image fluorescent responses at a particular wavelength has previously been demonstrated to be a sensitive method for detecting different organic materials. This device will allow tests to be conducted in commercial food processing facilities. The goal of these tests is to determine the operating parameters that should be incorporated in a commercial, user-friendly, imaging system. This device will be of interest to scientists, regulators, and commercial entities concerned about food safety.
Technical Abstract: 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 VIS 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 set and display camera gain by wavelength. This ability allows identification of response regions where ambient illumination intensity is low, commonly around 475, 520, and 675 nm. A principle goal is to acquire data to support development of a commercially-viable, hand-held, imaging system.