Reference for Chullin 206:15

וריש לקיש אמר פטור אכילה במעיו בעינן וליכא

Said R'Papa: As to that which remains between the teeth they certainly do not disagree,<span class="x" onmousemove="('comment',' All hold that it cannot be reckoned together with that which has been swallowed, for neither the gullet nor the stomach has derived any enjoyment therefrom.');">⁸</span>

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