There’s a secret chamber somewhere in the city, deep in the bowels of a busy restaurant, concealed behind drywall and piping. It’s dark inside, and only the hum of a small humidifier drowns out the knife work of the nearby prep cooks. It’s about the size of a coat closet, a coat closet that smells of aging meat. In the gloom, four large prosciutto-style hams are hanging from the ceiling, along with some chunks of coppa and a grayish dry-cured sausage that the overworked chef who built this room admits “isn’t working out.” On the floor there’s a box filled with more coppa.

Check out three of our favorite spots for in-house charcuterie

Billy Pork happened.

He went on to work at a packinghouse and took courses in food safety, but in 1996 a major change in the way the federal government regulated meat and poultry production was passed. Known as the “Mega Reg” of 1996, it instituted a vast new set of rules meant to control pathogens and made mandatory for producers what is known as hazard analysis and critical control point plans, or HACCP plans.

Word of mouth spread, and Nolen began taking on more restaurant clients, essentially scaling down the plans he’d written for large, industrial-size meat producers to relatively boutique-size restaurant kitchens and artisan operations, including the spotless, USDA-inspected fermenting and drying rooms at West Loop Salumi. Designed by a company that builds labs for pharmaceutical companies, the operation essentially falls under the same kinds of regulations as the giant Vienna Beef plant.

Every month or so Nolen teaches two-day basic and advanced HACCP classes at Lawry’s the Prime Rib or Sun Wah BBQ, the latter a favorite restaurant and a favorite client that has had its share of problems with the Health Department over the years, frequently over the temperatures the food in the front windows is stored at.