**7. Prevent the bitterness of whole grain flour**

The whole grain rye is beneficial for health. However it may be bitter. The impact of nonvolatile chemical compounds on the bitter taste of rye was analyzed by the aid of enzymatic hydrolysis, releasing potentially flavor-active compounds from the rye matrix. Water suspension of whole grain rye flour was treated with hydrolytic enzymes, after portions of the rye suspensions were baked into crackers and assessed for their sensory profile as well as solubilized hydrolysis products. Heat treatment reduced the perceived bitterness. The treatment with enzyme preparation with high protease activity increased the bitterness of rye and also wheat flour both as suspension and as crackers. Other enzymes tested (with high polygalacturonase, endo-glucanase, xylanase, or amyloglucosidase activity) had no significant impact on the perceived bitterness. Thus, small molecular weight peptides were considered to be a significant contributor to the bitter note of rye [53].
