Ultraviolet-C (UV-C) light technology has been proven efficient for reducing microbial counts in food. For industrial applications, processes have to be validated considering microbial and chemical safety. Hydroxymethylfurfural (5-HMF) can be formed in sugar-containing products and has been identified as possibly carcinogenic to humans. The effect of UV-C treatment at 254 nm on 5-HMF content in high fructose corn syrup (HFCS) and model sugar solutions was studied at doses from 50-250 mJ cm(-2). Absorbance spectra, pH, color and soluble solids content were measured. 5-HMF content was reduced by 43-62% in fructose syrups at 250 mJ cm(-2). Higher initial 5-HMF concentration yielded a higher reduction rate and pH had no effect on reduction. UV-C light reversed caramelization changes in syrup color and odor. Aside from indicating that non-thermal UV-C processing may contribute as a purification technology, these results are important for its validation and acceptance and for the chemical safety of syrups. Crown Copyright (C) 2016 Published by Elsevier Ltd. All rights reserved.