In short, all the Keilim (vessels) become suspected to be treif (non-kosher), and without a koshering process that status remains forever.
If you listen here, you might find some reasons to be Meikal (lenient), however that would only be in a bedieved (post ipso facto) situation.
Please find a YouTube Video here that shows actually scrapple being thrown into the mash tun.
In conclusion, being that there is a plethora of amazing craft beer out there one would be wise to stay away from Dogfish Head and other craft breweries that brew with non-Kosher ingredients.
The CRC who are the foremost Kashrus Agency when it comes to alcohol, have said to stay away as well.
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