For the retail operation, such as it is, of Best Provision in Newark, park in front of the formidable-looking brick building on Jelliff Avenue, scamper up the loading dock and muscle aside the heavy gray swinging door.

Vegetarians, beware. The 80,000-square-foot plant — one giant refrigerator, with temperatures at 40 degrees or cooler — is fragrant with the earthy, funky aroma of raw and cooked meat. Workers operate machines with oddly poetic names — choppers, shrink tunnels and the Frank-a-Matic, which stuffs, shapes and sizes hot dogs. A shiny space-capsule-like contraption is used for brine distribution.

“In July, we’re packing out 100 pounds (of hot dogs) a minute, all day,” Rich Dolinko says.

Where’s the beef? It’s right here; Best Provision, celebrating its 75th anniversary this year, is the food icon most Jerseyans have never heard of. The company doesn’t produce chicken, pork or any other meat; it’s hot dogs, pastrami, corned beef, roast beef and brisket — all beef, all the time.

Rich Dolinko, co-owner, Best Provision.

Best may be “America’s #1 manufacturer of private label cooked beef products” — clients include ShopRite, Stop & Shop, Wegman’s, Wal-Mart, Smashburger and others — but it keeps a famously low profile. Best also supplies franks to scores of hot dog storefronts, trucks and carts in and beyond New Jersey — but the operation itself is shrouded in CIA-worthy secrecy.

“We’re very private,” co-owner Kevin Karp says in a bare-bones conference room. “We don’t seek publicity. We’re pretty simple people.”

In 1938, Karp’s grandfather, Saul Karp, opened a wholesale and retail deli on William Street with Joe Wolfiler and Paul Dolinko. Back then, sandwiches were a dime, bologna and franks 25 cents a pound, and corned beef and pastrami 69 cents a pound.

“Started as a butcher shop,” says co-owner Rich Dolinko, Paul’s grandson, who oversees Best’s production side. “They made meat in the basement at night. Over the years, we kept adding on.”

And the secret to this family-owned business staying in business and in Newark for three-quarters of a century?

“We’re here because of the water,” Karp says, smiling. “Newark water is the best water in the country. Remember all the breweries (were) once located here.”

It may not look glamorous, but the Best Provision entrance on Jelliff Avenue is where to pick up your hot dogs.

The plant never shuts down during the week; there is always meat to be delivered, prepared, chilled, cooked. At the small retail counter, closed only on Sunday, all-beef hot dogs — skinless and natural casing — beckon. You know the old-timers and hot dog doyens by their coded language — W8, for the eight-to-a-pound hot dog once sold at Woolworth’s; B11 for the 11-to-a-pound dog sold at Bamberger’s.

Beyond the counter, in a seemingly endless series of rooms, white-jacketed, white-helmeted, white-booted employees — they look like extras in a sci-fi movie — work with meat of all shapes and sizes, from slabs of round to cake batter-like ground-up beef for hot dogs.

In one room, links are fed through a Rube Goldbergian complex of belts, conveyors, ramps and funnels. Even here, toward the end of the production process, the temperature is bone-chilling.

“We believe in cold,” Dolinko says. “The colder it is, the better it is for the meat, the environment and the quality.”

The beef comes from about a dozen suppliers, including National Beef Packing in Kansas City.

“Certain plants get certain kinds of cattle,” Dolinko says. “That National plant gets beautiful cattle.”

Best, according to Karp, is one of four supermarket “premium” hot dog brands in the metropolitan area, with Sabrett, Nathan’s and Ball Park. Best uses the same recipes Karp and Dolinko’s grandfathers did in 1938, and still makes deliveries to loyal customers.

“We’ve been running down to Joe-Joe’s in Toms River for years,” Karp says.

The tour over, Karp and Dolinko talk trends in the conference room. Hot dog sales were up 17 percent this fiscal year over last. The average hot dog-devoted supermarket shelf is eight feet long. Roast beef is hot, business-wise. Jersey likes its roast beef medium rare; as you go north, it’s rarer, as you go south, it’s cooked more.

There are no plans to move or expand; Karp and Dolinko like the old brick building on Jelliff Avenue just fine.

“We’re neighborhood,” Karp says. “We’re here 75 years. Must be doing something right.”

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