2,122. The Seven Detergents

Hilchos Issurei Biah 9:37

These are the seven “detergents,” which are applied in this order: tasteless saliva, chewed beans, stale urine, lye, natron, cumin and bleach. The stain is rubbed three times with each of these; it must be passed back and forth while rubbing. If one didn’t use these treatments in their prescribed order, or if he used all of them at once, he has accomplished nothing. If he used the later “detergents” before the earlier ones, the fact that he ended with the earlier ones in their proper order is significant because he may then use the later ones again, with the result that he has used all seven in order.

Hilchos Issurei Biah 9:38

“Tasteless saliva” means from one who didn’t eat from the beginning of the night. He slept the second half of the night and contributed his saliva before eating the next morning. He also must have not spoken too much during the first three hours of the day. If someone got up in the morning and reviewed his studies before three hours of the day, his saliva is not used because speaking cancels out the saliva’s power and makes it just like water. “Chewed beans” means beans that were well chewed so that they have been mixed with a large volume of saliva. “Stale urine” means that it’s three or more days old.