[Avodah] : Chometz milking question

[Micha Berger]

On Wed, Apr 13, 2011 at 08:32:19AM +0300, Eliyahu Grossman wrote:
: Just because Chometz is part of the input, that doesn't mean that the output
: takes on the same characteristics...

This is not so simple. The question of whether milk made by a cow eating
chameitz is actually two inyanim:

1- There is a general rule about 2 goremim -- the chameitz and the cow
being two goremim for the milk.

The SA (YD 142:11) holds that shnei hagoremim is "mutar bekhol maqom".

The Magein Avraham (445:5) and the Taz say that this doesn't apply to
chameitz, where we uniquely worry about less than a kezayis.

The Shach, the Gra, the SA haRav (445:10) and the Bi'ur Halakhah (s"q 2)
are meiqilim.

The Shaarei Teshuvah is the origin (?) of the idea of invoking bitul
before Pesach to satisfy even the MA and the Taz. See also the Igeros
Moshe, OC 1:147.

2- Returning back to /on/ Pesach... the Peri Megadim invokes an entirely
different inyan -- that if the cow ate chameitz within 24 hours of
milking, using the milk would be hanaah from something only due to that
chameitz. The MB (448:33) permits as long as the cow didn't /only/ eat
chameitz. The QSA (117:13 -- from today's QSA yomi) cites shitos both
ways, and advises "shomeir nafsho yachmir", estpecially when this is
the minhag hamaqom.

Tir'u baTov!
-Micha

-- 
Micha Berger             When you come to a place of darkness,
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