Abstract: Starch and protein in wheat bran were degraded into soluble contents by α-amylase and alkaline protease respectively,and then the soluble contents were removed by water-washing method to produce pentosan.The optimal parameters for hydrolyzing starch are:material to liquid ratio 1:12(g/ml),addition of enzyme 0.08 g,time 25 min,and temperature 95 ℃.The remained content of starch is reduced to below 0.5 % from original 18.6 %.The optimal parameters for hydrolyzing protein are:time 4 h,temperature 40 ℃,solid to liquid ratio 5%(g/ml),addition of enzyme 1.0%.The remained content of protein in destarched wheat bran is only 0.62%.The destarched and deproteined wheat bran contents 34.51% pentosan.

Key words: pentosans, starch, protein