Serious Eats: Sweets

Secret Tools and Tricks of the Ice Cream Pros: How to Make Creamy Ice Cream

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Lauren Resler's amaranth ice cream. [Photograph: Brent Herrig]

What are your biggest problems making ice cream at home? When I talk to home cooks, I hear one issue again and again: how do you nail a perfect creamy texture that doesn't freeze up like a brick or turn icy over time? What do restaurants and ice cream makers get right that we're getting wrong?

The pros have a few advantages on their side. Some are obvious—heavy-duty machines, say, or super-cold freezers—equipment you could only dream about unless you had $20,000 burning a hole in your pocket. But plenty of their tools and techniques would be perfectly at home in your kitchen or mine: good storage practices, natural stabilizers like gelatin or pectin, or alternative sugars you can order online and get delivered to your door.

I spoke with nine ice cream pros, a mix of pastry chefs and ice cream specialists, to see how they keep their ice cream smooth and creamy. Here's what they had to say, and what secrets you can steal for your own recipes.

The Machine

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[Photograph: Laura Togut]

Most consumer-grade machines have a removable core that chills in a freezer and can only churn one small batch a time. Professional machines, on the other hand, range from the size of a small air conditioner (with a similar built-in compressor) to that of a free-standing fridge. One popular brand that comes in a range of models is a Carpigiani batch freezer, the Lamborghini of ice cream makers, with five-digit prices to match.

"The Carpigiani is very fast and efficient," says Julian Plyter of New York ice cream sandwich company Melt Bakery, where he churns gallons of ice cream at a time. Once his machine is up to speed, he can spin a batch in about ten minutes, a must for keeping labor costs under control. (Imagine paying someone to churn a single quart of ice cream every half hour!)

Fast freezing also means smaller ice crystals, one of the keys to creamy ice cream. And in a commercial American-style batch freezer, paddles rapidly whip air into the base, adding a discernible fluffiness to the end result. At home, my vanilla ice cream is creamy and rich; when spun in a Carpigiani batch freezer, it's spectacular: full-bodied and unbelievably smooth.

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Tracy Obolsky's rice pudding ice cream sundae at North End Grill. [Photograph: Jacqueline Raposo]

But most restaurants can't afford to drop tens of thousands of dollars on a super-fancy ice cream robot. That includes Tracy Obolsky, pastry chef of North End Grill in New York, and former SE contributors Anna Markow (pastry chef of New York's Amali) and Stella Parks (formerly of Table Three Ten in Lexington, Kentucky), who use smaller countertop machines. The main virtue of these models, which run several hundred to over a thousand dollars, is their ability to make batches of ice cream back to back, nice for a restaurant that only needs more than a couple quarts of ice cream at a time, but less than 30 gallons.

Do these fancy machines make better ice cream? Quite possibly, but if you're thinking of investing, consider that a $750 machine doesn't make ice cream that's 15 times as good as a 50 version. You're paying for speed and output as much as quality.

Pastry Chef Tracy Obolsky at North End Grill

Tracy Obolsky. [Photograph: Jacqueline Raposo]

It's also worth remembering that good ice cream machines don't make good ice cream; people do. "I use the same recipes at home that I do at work," Obolsky tells me. "They're a little looser and icier in my little Cuisinart, but they definitely get the job done for home eating."

The takeaway: Ice cream pros have better machines than you do, but their needs are also different than those of home cooks. Don't envy a $1,000 machine if you aren't making gallons of ice cream at a time.

The Freezer

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Meredith Kurtzman's Gelato at Otto. [Photograph: Brent Herrig]

If you're looking for the single greatest advantage pros have over come cooks, don't look to the ice cream machine—look to the freezer.

"The biggest key for good ice cream is keeping everything very cold," says Plyter, which is why as soon as his ice cream comes out of the machine, it goes straight into a chest freezer that maintains subzero temperatures. By contrast, most home freezers are relatively warm, and their automatic defrost cycles slowly melt and re-freeze ice cream.

Scoop shops and restaurants often have separate service freezers that warm the ice cream up to a softer, more scoopable temperature, between 0 and 10 degrees Farenheit. But once ice cream enters the service freezer, that's it—it should be kept there, eaten, or melted down, as repeated trips between storage and service freezers can make for icier ice cream.

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Meredith Kurtzman. [Photograph: Brent Herrig]

That's not to say all the pros have it easy. At New York's Otto, gelato master Meredith Kurtzman doesn't have a super-cold blast freezer at all, so she adapts her recipes to handle relatively warm freezer temperatures. Parks had the opposite problem at Table Three Ten—they only had a subzero freezer—so she altered her recipes to be scoopable at -23°C. At New York's Empellon restaurants, pastry chef Lauren Resler times her freezer's mechanized defrosting cycle to align with the evening's dinner rush—a tricky feat of planning and training her staff.

The takeaway: The single biggest investment you can make in your ice cream is keeping it cold. Here's how; or hey, you can pick up a small chest freezer for about $250.

Stabilizers

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[Photograph: J. Kenji Lopez-Alt]

Repeat after me: processed stabilizers don't make bad ice cream. Bad technique makes bad ice cream.

Don't believe me? Then ask Kurtzman, who adds a proprietary blend called Sevarome as well as milk powder and maltodextrin to many of her bases. Or Plyter, who uses such a small amount of plant gums in his recipes that the first time he blind tasted a sample, he didn't realize it was stabilized at all. Resler likes the slight chewiness guar gum adds to ice cream and the creamy texture xantham gum lends sorbet. Atlanta's High Road uses different stabilizer blends depending on each recipe, and even Southern Craft, an excellent—and purist—farmstead ice cream company, employs some gelatin.

"People need to stop thinking stabilizers are evil," says Kurtzman, who relies on them at Otto to manage the heat shock her ice cream endures from less-than-ideal storage conditions. But just as stabilizers don't guarantee bad ice cream, they aren't necessary for good ice cream.

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An ice cream sandwich from Melt Bakery. [Photograph: Robyn Lee]

Some pros just prefer to avoid them, like Obolsky at North End Grill. For Parks, "over-reliance" on syrups, stabilizers, and emulsifiers "limits creativity." At Amali, Markow eschews most refined stabilizers in favor of whipped meringue or fruit pectin in sorbets. There's no right or wrong answer when it comes to stabilizers, just the pro's personal preferences and kitchen needs.

The takeaway: Stabilizers are just one of many tools in an ice cream maker's arsenal, and every pro has their own preferences. What do they all agree on? If you use stabilizers, use them sparingly.

Alternative Sugars

Liquid sugars drastically impact ice cream and sorbet texture. [Photograph: Robyn Lee]

Most home ice cream recipes call for simple table sugar, which is chemically known as sucrose. But in pro kitchens you have more options. Liquid sugars like invert sugar, corn syrup, honey, and glucose syrup all add body, creaminess, and stability to ice cream, and a little goes a long way.

For Kurtzman's gelato, "every recipe is different." Some bases rely solely on sucrose while others supplement with glucose or trimoline. "We generally use white sugar," Plyter tells me, "but sometimes we use a 1:4 ratio of glucose to sucrose for texture."

There are more reasons than texture alone to consider alternative sweeteners. Says Parks, "Sometimes I'll supplement a base with barley malt syrup, honey, molasses, or maple syrup to add depth of flavor."

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[Photograph: Robyn Lee]

It's easier than ever to get your hands on alternative sugars, and if you're serious about your ice cream, they're worth seeking out. Corn syrup is the most readily available, but others like glucose syrup and glucose powder are easy to find online. They don't just add body; they also make ice cream more resilient to melting and re-freezing, a godsend for those cursed with finnicky freezers.

A note of caution: different sugars have different levels of sweetness, so if you're supplementing your sucrose with other sugars, check out this chart (PDF) to see how they compare to table sugar.

The takeaway: Small doses of alternative sugars, when used wisely, can make for creamier, more full-bodied, and stable ice cream.

Shelf Life

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Lauren Resler. [Photograph: Brent Herrig]

Like bakeries, ice cream shops and restaurants have the benefit of high turnover. Ice cream can turn stale like anything else, and the faster it's eaten, the better. So at Otto, for instance, a batch of gelato lasts about three days.

A pro's needs and equipment determine how long they'll keep ice cream around. At Melt Bakery, ice cream that's left undisturbed under subzero chill in a chest freezer is good for months. For a pastry chef like Resler, who deals with smaller volumes of ice cream, it makes more sense to melt down the night's leftovers and re-spin them the next day.

The takeaway: Melting and re-freezing makes good ice cream go bad, and it's somewhat unavoidable in home freezers. The best solution? Eat your ice cream quickly.

A Radical Departure

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Minutes-old ice cream at Smitten. [Photograph: Max Falkowitz]

There's another technique more and more pros are adopting to make great ice cream: liquid nitrogen.

The idea is simple: if deep chill and fast freezing times make for the creamiest ice cream, why not make ice cream using the coldest, fastest freezing ingredient around?

That's what Robyn Sue Goldman does at Smitten in San Francisco. When you order a scoop of ice cream, a liquid base is poured into a mixing bowl and whipped with specially designed beaters while liquid nitrogen is poured on top. The ice cream freezes in a matter of minutes, and it's incredibly smooth with a spoonable, gelato-like consistency.

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[Photograph: Max Falkowitz]

"By making every batch to order, we can throw everything out the window. The ice cream doesn't sit around and we don't need to worry about shelf life," says Goldman. That also means no need for stabilizers, alternative sugars, or in some cases even egg yolks, which emulsify and stabilize custard ice creams but also obscure bright flavors.

Making liquid nitrogen ice cream at home isn't easy, and not just because there's limited public access to the star ingredient. "The nitrogen freezes the ice cream so fast," Goldman tells me, "that you need to agitate it right so it doesn't clump up." Her machine uses two special beaters that wipe down everything—the sides of the bowl and the beaters themselves—to ensure a completely consistent texture. But hey, if you have a stand mixer and some liquid nitrogen on hand, go ahead and give a homespun version a try. You'll certainly have a fun party trick.

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[Photograph: Max Falkowitz]

Liquid nitrogen ice cream shops are few and far between today, but they're growing, so don't be surprised if you see more popping up in the coming years. And who knows, maybe some day we'll see consumer-grade LN2 machines at Sur La Table right next to conventional ice cream makers.

Any Questions?

Have more questions about making pro-level ice cream? Ask away in the comments, and check out some of these links:

About the author: Max Falkowitz is the New York editor and ice cream maker in residence at Serious Eats. You can follow him on Twitter at @maxfalkowitz.

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