Germ and outer layers
of the caryopsis have higher enzyme activities. Particular lipase, but
also lipoxygenase and peroxidase, are probably most important
commercially because they effect the keeping quality and shelf life
of rice bran (Orthoefer, 2005). Ramarathnam, Osawa, Namiki, &
Kawakishi (1989) also reported that lipid peroxidation by lipases
and lipoxygenases is thought to be the primary cause for bran
degradation.