"You don't pound it like a regular beer, you just sip it," Koch adds.
In 2017, only 68 casks were produced, creating 13,000 bottles available for purchase.
There's just one catch: The brew is illegal in 15 states in the U.S., including Alabama, Arkansas, Georgia, Idaho, Missouri, Mississippi, Montana, New Hampshire, North Carolina, Oklahoma, Oregon, South Carolina, Utah, Vermont and West Virginia, according to the Sam Adams site.
Koch says it's illegal "because of the high alcohol [content and] the unique brewing process," which he calls the "lunatic fringe of brewing."
"As a brewer, I'm okay with that," Koch tells "Secret Lives of the Super Rich." "To me, there's only one thing better than great, wonderful beer — it's great, wonderful beer that's illegal."
Watch new episodes of CNBC's "Secret Lives of the Super Rich" Wednesdays at 10P/ET.
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