We may not soak bran for chickens, but we may scald it.  A woman may not soak bran to take with her to the baths, but she may rub it on her skin dry.  A man may not chew wheat and place it on his wound on Pesach, because it becomes chametz.

Flour may not be put into the charoses nor into the mustard. However, if one did put it [in], it must be eaten immediately; but R' Meir forbids [it]. We may not cook the pesach-offering neither in liquids nor in fruit juices. But we may baste and dip it in them.  The waters used by a baker must be poured out, because they become chametz.

These must be removed on Pesach: Babylonian kutach, Median beer, Idumean vinegar, Egyptian zisom, dyers' broth, cooks' dough and scribes' paste. R' Eliezer says: also women's cosmetics.  This is the general rule: Whatever is of a species of grain must be removed on Pesach. These are in the category of a prohibition but they are not subject to kares.

When dough remains in the grooves of a kneading trough, if there is as much as an olive's [volume] in one place, he must remove [it]; but if not, it is null because of its insignificance. And likewise regarding the [laws of] contamination. If he objects to it, it interposes; but if he desires it to remain, then it is as the trough.  [Regarding] “deaf” dough, if there is [dough] similar to it that has already leavened, it is forbidden.