Vic, it is possible something like this UV torch on ebay might work, if it is bright enough.
http://cgi.ebay.com/21-UV-LED-Ultra-Violet-Black-light-Flashlight-395-nM_W0QQitemZ220078734092QQihZ012QQcategoryZ66954QQrdZ1QQcmdZViewItem
Quite a few items on this website also:
http://www.blacklight.com/
When our boxer pup was young, the wife wanted her to stay in the house, so I bought one of those small 6 inch battery operated uv tube black lights at the pet store to detect the stains from the pup -- but it was too weak for that purpose and far to weak to illuminate the corn. My son had a 12" flourscent fixture with a black light tube in it that had to be plugged into a regular power source. That one worked like a charm for revealing the molds and fungi on the pigeon feed -- and for finding pet stains. If you see one in a store, make sure it shines brightly or it is worthless.
Larry