[Avodah] timtum halev

[Rich, Joel]

If some treif substance is batel is there any reason not to eat the combination because it contains some treif substance which will cause timtum halev. How because it is allowed to be eaten does it remove timtum halev 
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IIRC It's a machloket - some say that you should eat it because those sparks in the previously treif portion were meant to be raised by your eating (pls don't ask me what that means), others say there is no timtum because halacha determines reality, others say yes timtum because there is some element of treif.
B"N I'll look for the sources at home.
KT
Joel Rich
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