Why bread?

Hi,

We have offered two sources for the practice of netilat yadayim (hand-washing) before eating bread:
1) Preparation for terumah-tithe, and
2) Cleanliness.

Although terumah applies to more than bread, and although cleanliness applies to more than bread, we wash and recite a berachah only for bread. This is because:

1) Re: terumah - the main form of terumah is grain, which is generally made into bread;
2) Re: cleanlienss - the main concern was for cleanliness at a meal, and meals center around bread.

(Mishneh Berurah 158:2; Sha'ar haTziyyun 158:3)

Have a great day,
Mordechai