ARS | Publication request: PORTABLE HYPERSPECTRAL FLUORESCENCE IMAGING SYSTEM FOR DETECTION OF BIOFILM ON STAINLESS STEEL COUPON

Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: March 24, 2008
Publication Date: April 23, 2008
Citation: Jun, W., Lee, K., Millner, P.D., Sharma, M., Chao, K., Kim, M.S. 2008. Portable hyperspectral fluorescence imaging system for detection of biofilm on stainless steel coupon. BARC Poster Day, Beltsville, MD, April 23, 2008.

Technical Abstract: Portable hyperspectral fluorescence imaging, as a rapid nondestructive method, was used to investigate detection of bacterial contamination on the surfaces of food processing equipment. In this study, stainless steel plates typically used to manufacture food processing equipment was utilized to grow microbial biofilm for evaluation of bacterial contamination. Biofilms were formed by immersing stainless steel coupons in bacterium cultures, such as E. coli, Pseudomonas pertucinogena, Erwinia chrysanthemi, Listeria inoocula for a 1-week. Biofilm formations on coupons were then assessed using fluorescence imaging. Biofilm formation levels in both tryptic soy broth (TSB) and M9 medium with casamino acids (M9C) were examined. TSB grown cells enhance biofilm production compared with M9C minimal medium grown cells. Portable hyperspectral fluorescence images of the biofilm samples, in response to ultraviolet-A (320 to 400 nm) excitation, were acquired from 425 to 700 nm. Visual evaluation of individual images at emission peak wavelengths in the blue-green demonstrated the most contrast between biofilms and stainless steel coupons. Two-band ratio (i.e., 444/588 nm) compared with the single-band images increased the contrast between the biofilms and stainless steel coupon surfaces. Supported by USDA ARS CRIS Project No. 1265-42000-013-00.