2026-09-22T11:07:43Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/130224 2026-02-10 col_2142_5131 col_2142_14781 com_2142_5130 com_2142_687 com_2142_397

application/pdf en text Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-08-01 The student, Abdullah Bin Murayshid, accepted the attached license on 2025-07-23 at 16:20. The student, Abdullah Bin Murayshid, submitted this Thesis for approval on 2025-07-23 at 17:08. This Thesis was approved for publication on 2025-07-24 at 16:52. DSpace SAF Submission Ingestion Package generated from Vireo submission #22714 on 2025-10-25 at 15:54:34 Effectiveness of far-UVC 222 nm on Escherichia coli o157:h7 and Listeria monocytogenes across different fresh produce surfaces Bin Murayshid, Abdullah Ali A. 2025-07-24 Wang, Yi-Cheng Miller, Michael Banerjee, Pratik Far-uvc 222 Nm Fresh Produce Krypton-chlorine eng The objective of this study was to evaluate bactericidal activity of far-ultraviolet C (far-UVC) light at 222 nm against Escherichia coli O157:H7 and Listeria monocytogenes on fresh produce with different surface types and characteristics, romaine lettuce and strawberries. Inoculated samples were treated with increasing far-UVC doses (0–210 mJ/cm²) using a krypton-chlorine excimer lamp. Microbial inactivation was measured as a log CFU/g reduction and surface roughness of each sample was determined by 3D optical profilometry. Far-UVC treatment produced larger reductions on romaine lettuce (2.47 log CFU/g for E. coli; 2.33 log CFU/g for L. monocytogenes) compared to strawberries (1.30 and 1.49 log CFU/g), which was anticipated based on romaine lettuce having a smoother surface (Sa: 3.568 µm) compared to a more rugged strawberry surface (Sa: 36.722 µm). Microbial inactivation showed to be influenced by surface properties. Far-UVC exposures did not significantly affect the CIELAB color parameters taken before and after treatment, which suggested minimal harm to the produce as far as visual quality is concerned. This research contributes to the knowledge about the practical role and usefulness of 222 nm far-UVC to improve microbial safety on fresh produce, while allowing for visual as well as marketable appearance of products without chemical or thermal treatment. 2025-08 Text https://hdl.handle.net/2142/130224 Copyright 2025 Abdullah Bin Murayshid Food Science & Human Nutrition Food Science & Human Nutrition University of Illinois Urbana-Champaign M.S. Thesis