June 9, 2021

For six years, Jessica Rooney has been bringing innovative frozen confections to the Sioux Falls metro area, from shaved ice at Dakota Snow to rolled ice cream at Sub Zero Desserts. On Monday, she launched a twist on frozen treats at The Empire Mall: nitrogen ice cream.

Sub Zero Nitro is in the mall’s food court between Cinnabon and Charley’s Philly Steaks. The shop offers mini, regular and waffle bowl sizes of its unusually made ice cream that is prepared fresh for each customer in a matter of seconds.

The key to how quick the ice cream is made? Liquid nitrogen. 

Once a customer orders, workers take an ice cream base, add flavoring and toppings to it and then pump in liquid nitrogen while wearing special gloves for safety. The nitrogen instantly freezes the base, leading to quick, easy and delicious ice cream. 

Rooney said there are many benefits to making ice cream using liquid nitrogen. Besides how fast it takes to make it, the instant freeze leads to a richer taste and creamier texture.

“Even when it sits in your freezer, you know, normal ice cream is almost like a rock, and it’s sitting in your freezer for four months or whatever,” Rooney said. “Just the other day, we made beer ice cream using nitrogen, and my husband got out the little thing — so creamy, still soft, like so good. And so there’s just something about making it with the nitrogen. It keeps those ice crystals out, and so it stays fresh really long, but it’s so rich when you first get it.”

Rooney said Sub Zero Nitro will be in the food court at least through the end of August, though it has the option to stay longer depending on how the summer goes. 

She said she is unaware of any vendor selling nitrogen ice cream anywhere else in the state and loves the exposure of having a storefront in The Empire Mall food court. 

“We love being the first,” she said. “We were the first with, for the most part, having a regular shaved ice stand, nobody had done it here with the ice cream in them and all the toppings. We were the first for the rolled ice cream, and now we’re the first with nitrogen. We love that aspect of bringing something new to our community that’s fun and exciting.”