Reference for Chullin 30:9

פעמים שהשוחט מותר כגון שהיה לו חולה מבעוד יום מבשל אסור כגון שקצץ לו דלעת

And in certain cases even when a man cooked [for one who fell ill on the Sabbath], it may not be eaten [by a healthy person], e.g. , where a pumpkin was plucked [out of the ground on the Sabbath and cooked].<span class="x" onmousemove="('comment',' It is forbidden to be eaten because of mukzeh, since on the eve of the Sabbath the pumpkin was still attached to the ground. Cf. however Tosaf ad loc.');">⁸</span>

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