Lipoic acid was found to be present at low levels in wheat germ (ca. 0
.1 ppm) but was not detected in flour or semolina. The reduced form of
lipoic acid provided the reducing equivalents for thioredoxin in the
reduction of proteins of wheat endosperm (albumins, globulins, gliadin
s, and glutenins). The results indicate that, while lipoic acid could
function to reduce thioredoxin physiologically, its importance to tech
nologies based on flour or semolina is questionable.