Before setting sail, the yacht’s crew blowtorched the ovens, sterilized the silverware and swapped out the china under a rabbi’s watchful eye. At sea, they prepared meat and dairy dishes in separate kitchens and served them in separate rooms, accompanied by kosher wine. The ship’s conference center became a synagogue; the Sabbath was celebrated in a spacious lounge. Cabins have key locks to avoid the use of electronic devices on the Sabbath. The theme of last week’s cruise: “Cordon Bleu Goes Kosher,” featuring wine tastings and cooking demonstrations. “There will not be any overblown Vegas-style shows,” says company CEO Matthew Shollar. “We’ve taken a dignified, interactive, educational approach.”