Reference for Chullin 217:10

ניער בסוף ולא ניער בתחלה כסה בסוף ולא כסה בתחלה מותר

It is evident then that they hold that when the forbidden substance can be considered extracted it becomes permitted.<span class="x" onmousemove="('comment',' Hence we see that where the forbidden substance can be considered extracted is a matter of dispute between Tannaim.');">⁶</span>

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