Lightstruck

Lightstruck. (layt'-struhk)

An unpleasant flavor in beer caused by exposure to light, resulting in undesirable chemical reactions of hydrogen sulfide and other sulfur compounds with a side chain of the iso-humulones and the formation of phenyl mercaptan (3-methyl-2-butene-1-thiol), which imparts a skunklike flavor.

Syn: sunstruck