Alkemy in Huntington makes liquid-nitrogen ice cream 

Alan Lacher vividly recalls the time his high school chemistry teacher demonstrated the states of matter — gas, liquid, solid — by using liquid nitrogen to produce ice cream. Exposed to the air, the nitrogen immediately vaporized, blasting the mixture of milk and sugar with such cold force that it froze immediately.

“The ice cream wasn’t very good,” he recalled. “But the demonstration stayed with me.”

Now he has perfected that science experiment and, at Alkemy in Huntington, he deploys the same basic technology to custom-create individual portions of ice cream. Patrons choose one of a dozen liquid bases (among them, vanilla bean, milk and dark chocolates, cold-brew coffee, mint, banana and dulce de leche) and an “alkemist” stationed behind a heavy-duty standing mixer releases the harmless gas (it makes up 78% of our atmosphere) into the rotating bowl. By the time the vapor cloud has dissipated, the liquid has coalesced into a dense, rich ice cream. 

Lacher couldn’t have picked a better stage for his ice-cream theater: Alkemy occupies a corner at the intersection of Main Street and New York Avenue which was, for many years, an Aerosoles shoe store before it housed two short-lived bakeries, Crave and Cream.

The Huntington resident grew up to be a science-and-technology guy, creating software systems that large institutions — from insurance companies to school systems — relied on. But when he retired last year at age 50, he wanted to devote himself to something he loved, something that everyone loved: Ice cream.

“When I was in enterprise technology,” he recalled, “everyone seemed stressed out and miserable most of the time. Now I’m making a product that makes everyone happy.”

In creating Alkemy, Lacher didn’t entirely abandon his analytical approach to work. The liquid-nitrogen method appealed to him not only because it looked cool, but because it solved the essential challenge of making ice cream: How to freeze a liquid without having it crystallize. In traditional ice-cream production, the liquid “mix” (milk, cream, sugar and flavorings) is poured into a batch freezer which churns it as it freezes. The churning mitigates some of the crystallization, but not all of it: Emulsifiers and stabilizers — whether they are natural (egg yolks) or not (soy lecithin, guar gum, carrageenan) — must be added to the mix.

But liquid nitrogen freezes the liquid so quickly, it needs no emulsifiers, resulting in the pure flavor of whatever ingredients are used.

And here’s what got Lacher even more excited about his method: Instead of using a premade commercial ice cream mix (as do virtually all local ice cream shops), he could make his own from local dairy, sugar and whatever else he deemed delicious. Because he starts with milk and cream, he must pasteurize it on the premises, and that’s what he does in a little kitchen off the second-floor dining area. In the pantry next to the vat pasteurizers are containers of freshly made cold-brew coffee, Belgian chocolate, East African vanilla, fresh mint leaves, matcha tea and, for the fruit flavors, roasted strawberries and bananas.

No dairy? No problem. Lacher experimented with oat milk, coconut milk and others before settling on cashew milk (also made on the premises) to use for his vegan ice cream mix.

If Lacher is a purist when it comes to ice cream base flavors, he lets his hair down a bit when it comes to toppings. Bring on the M & M's, Gummy bears, Fruity Pebbles, cookie-dough bites and cinnamon-toast crunch — alongside walnuts, almonds, bananas and stroopwafel cookies. There are no cones here, but you can nestle your ice cream into a “bubble waffle,” which got its start as a Hong Kong street food (often called egg cake) but has a natural affinity for ice cream. You can craft your own sundae with hot fudge, dulce de leche, marshmallow cream, roasted strawberries or a hard chocolate shell. Alkemy also has signature confections such as s’mores (chocolate ice cream, graham cracker, torched marshmallow) or roasted strawberry (strawberry ice cream served with an injector of balsamic glaze).

Alkemy, 260 Main St., Huntington. Open Tuesday to Thursday from 4 to 9 p.m., Friday to 11 p.m., Saturday from noon to 11 p.m. and Sunday from noon to 9 p.m.; 855-255-3690, alkemyicecream.com