A former Air Force F-16 mechanic has leveraged his GI Bill-funded chemistry degree, along with military surplus gear stripped from nuclear test labs, to invent a brand-new way of making ice cream.
And it all started with a burrito. Well, not enough burritos, actually.
“My wife had opened a burrito franchise, but it wasn’t doing as well as we had hoped,” says retired Staff Sgt. Jerry Hancock.
This was back in 2004. Hancock, who’d already served in the Air Force Reserve, had just gotten his degree and after graduating reenlisted into the Utah Air National Guard.
He and his wife Naomi knew they needed to bring something different to beef up the Provo, Utah-based burrito business.
Customers told them ice cream would be cool. Sure, but how could they make it unique?
“We wanted something people would travel from miles around to come for,” he says. Hancock didn’t know anything about ice cream, but he figured he could put his chemistry degree to work figuring something out.
He thought using super-cold liquid nitrogen seemed like a promising way to transform cream and flavorings into that icy miracle of frozen goodness we all know and love.
And no, liquid nitrogen is not the same stuff Darth Vader used to freeze Han Solo — that was liquid carbonite, only available in sci-fi realms far, far away — but it's the same flash-freezing fuel doctors use to shrink metal ball joints to insert hip implants and scientists use to stress-test metal, among other applications. It certainly got things cold. Why not see if it you could make ice cream with it?
Hancock found a used cryogenics tank — designed to store liquid nitrogen — at an auction from a nuclear test lab in Idaho and went to work.
Four years later, and after a lot of trial and error, he’d not only perfected the process itself, but customers said it was the best ice cream they’d ever had. As the business and demand grew, Hancock kept tapping into the military surplus market for the needed equipment. "We’ve gotten cryogenic surplus from the Navy and Air Force. We got one tank from Redstone Arsenal.”
Hancock says customers love the ice cream because, at 321 degrees below zero, liquid nitrogen reduces the typical 18-hour process used by most ice makers down to just about 15 seconds.
More importantly, it requires far less stirring to make it.
Most ice creams are slowly churned in a process that introduces air into the air mixture as the cream is frozen. It’s what ice cream experts call “air whip.”
Most brands have an air whip factor of 50 percent, or even higher. “That means 50 percent of the ice cream is actually air,” he says. And more air means less taste.
The best, most premium brands can get that air whip factor down to is about 15 percent, he says. And that’s why your little tub of Ben & Jerry’s tastes so good, and costs so much.
“But we’ve got it down to close to zero percent air whip,” says Hancock with a note of pride in his voice.
His now patented process also means there’s no time for ice crystals to form, which rob ice cream of its of its creamy smoothness. You’ve probably noticed ice crystals in that half-eaten carton in the fridge. Those crystals are first formed when the ice cream is made. The longer it takes to make, the more crystals are created and the bigger they get, Hancock says.
By the time they show up as freezer burn in your fridge, the ice crystals have exploded in size from melting and then refreezing, but they’ve largely been there all along.
And because he was making the ice cream literally on the spot for each customer, that meant each batch could be truly customized not just with the kind of crumbled cookie, candy, fruit, and nut-mix taste boosters you’d find in a Dairy Queen or Cold Stone Creamery, but even the very flavor of the ice cream itself.
Even the type of cream itself is a choice, from a traditional custard or yogurt base to low-fat, lactose-free, vegan and sugar-free options.
The new ice cream was so popular that soon the burrito store was converted into the first Sub Zero Ice Cream shop, soon followed by another and then some more as the couple expanded the business into a franchise.
He’s experimented with other quick-freeze options. Dry ice doesn’t work because it melts into the cream, not only diluting “but also carbonating it, making it bubbly, and changing the flavor, but not in a good way. But we're still experimenting and refining what we do with the liquid nitrogen."
Whatever he’s doing, it’s working.
Now Sub Zero has more than 50 stores across the country, more than doubling in the last two years alone.
Jon Anderson covers life after the military. Email him at [login to see] .