How to Make Diet Ice Cream That Actually Tastes Good

Photo: halotopcreamery/Instagram

For years, Healthy Ice Cream has been the diet world’s parallel to the Fountain of Youth: a desire universally acknowledged but shrouded in myth, something glorious in theory but impossible in practice. Many have tried to find it, but their efforts have always ended up overly saccharine, icy, and, in some cases, downright offensive. I’ll just say it: Low-calorie ice cream is bad. For a very long time, it’s been the textbook definition of a failed experiment, a Frankensteinian monstrosity of slush and aspartame.

Then along came Halo Top. Perhaps it’s because the mission was so personal: Its founder, a former lawyer named Justin Woolverton, says that he came up with the recipe after deciding he wanted an ice cream he could eat guiltlessly by the pint, leaving his job to better dedicate himself to this noble task. The result? An ice cream that, health-wise, is like eating an energy bar, if not better. (A pint of Halo Top contains as much protein as a Clif Builder’s bar — 20 grams — and a third fewer carbohydrates.)

Taste-wise, Halo Top compares … favorably to a Clif Bar, of course. But does it taste like ice cream? On this front, people are somewhat divided — but if the numbers are any indication, Halo Top appears to do the job just fine. As of this month, it has become the best-selling pint of ice cream in the USA, out-selling both Ben & Jerry’s and Häagen-Dazs. Personally, I find Halo Top delicious, almost frighteningly so. How can this be healthy? I wonder every time I chomp my way through a pint of salted-caramel or birthday-cake or mint-chip. Am I being hoodwinked?

Curious about how they do it, I reached out to Woolverton, now Halo Top’s CEO. Woolverton is understandably guarded about his recipe, which he developed over many years of trial and error. But he was willing to share some of the broader strokes of the recipe he patented — and his answers, combined with past research on flavor science, give us a glimpse into what can turn a diet ice cream into something that convincingly mimics the real thing.

It’s fluffy.
One huge reason Halo Top is lighter than regular ice cream: It’s actually, literally lighter. Whereas one pint of Halo Top contains around 260 grams of ice cream, a pint of Häagen-Dazs contains about 408 grams of ice cream — nearly 40 percent more. This knowledge might be frustrating when you realize you’re paying $6 for less product, but hey, we pay for portion control all the time.

It has a smart amount of fat.
Turns out, we aren’t actually as good at detecting differences in fat in ice cream as we might think. In a study published earlier this year in the Journal of Dairy Science, participants sampled ice creams with varying fat contents and tried to differentiate between them; in some cases, they weren’t able to detect a fat difference of up to four percentage points.

This can be partially explained by the addition of maltodextrin, a thickening agent that mimics the texture of fat. Depending on how heavy your ice cream is, a 4 percent difference in fat could lead to a caloric difference of 36 calories per 100 grams of ice cream, or 154 calories per pint. While die-hard purists might reject low-fat ice creams out of hand (“Excuse me, I am trying to taste some fat here” wrote one redditor in response to the study), a lot of them probably wouldn’t be able to tell the difference if they didn’t know what they were eating.

To a point. There’s no trickery that would make a no-fat ice cream taste good, notes Bob Roberts, a food scientist at Penn State and one of the study’s authors. Most of the time, when a healthy ice cream messes up, it’s because they went too far, he notes. But Halo Top is still 3 percent fat: “It’s not a super low-fat product,” he says. “That is, it’s not zero, and having some [fat] makes a large difference.” By keeping some key elements like fat, Roberts says, manufacturers can substitute just the right amount of healthy or filler ingredients — like fiber, which adds bulk and holds water without adding calories. Milk protein concentrate plays a similar role, helping the ice cream achieve an optimal water content while adding protein.

Still, it appears that richness, not fat, is really what makes an ice cream great. And while Halo Top does have some fat, it mostly has richness. To make Halo Top creamy and low-fat at the same time, Woolverton used rich-tasting ingredients present in traditional ice cream, but he cut out the fattiest parts — more milk than cream, more egg whites than egg yolks, etc. And, he notes, quality matters: “Using extremely high-quality flavoring ingredients … really matters a ton and contributes to that creamy taste.” And also, probably, to that $6 price tag.

It’s not as sweet as you think it is.
In addition to a small dose of real cane sugar, Halo Top includes liberal amounts of the calorie-neutral sweetener stevia. For texture as well as taste, says Woolverton, it also includes erythritol, a sugar alcohol that is naturally found in fruits, vegetables, and fermented foods. Erythritol tastes almost as sweet as sugar, but it doesn’t affect blood sugar and it’s not processed as a carbohydrate (don’t eat too much of it, though — it can act as a laxative in large amounts).

A note on artificial sweeteners, because they are confusing. As with many other nutritional innovations we’ve come up with in the last few decades, the jury’s still out on the long-term repercussions of artificial sweeteners. So far, however, scientists have failed to establish any direct links between the artificial sweeteners condoned by the FDA and metabolic disease. Several studies have linked artificial sweeteners to obesity, diabetes, and other health issues (aspartame in particular), but most of these studies have correlation issues — for instance, people drinking aspartame-laden diet sodas were also eating a lot of added sugars and other unhealthy foods, which could have been the reason for their weight gain. (For more on the dubiousness of the link between diet sweeteners and health, check out Yvette d’Entremont’s piece on Diet Coke for the Outline).

Roberts notes that while Halo Top is low-sugar for an ice cream, it is still about 8 percent real sugar, which seems to be the amount necessary to keep the ice cream authentically sweet and creamy. Using sugar alcohols like erythritol also lowers Halo Top’s freezing point, which enables it to stay creamy at colder temperatures — but not quite the same way actual sugar would (Halo Top freezes a bit harder than regular ice cream).

And then there’s the sneakiest trick of all …

It numbs your taste buds.
Cold food numbs the taste buds just a bit, dulling our sensitivity to subtle flavors — which is partially why cheap beer can taste perfectly acceptable chilled, but almost undrinkable warm.

Still, cold cannot mask texture and mouthfeel, two things that are necessary for a truly great ice cream. As Roberts and his co-authors in the fat-percentage study write, ice cream is a “complex food matrix” of creaminess, sweetness, and mouthfeel, one that’s extremely difficult to alter in a substantial way without really screwing up. Ultimately, Roberts says, Halo Top is clearly the result of a lot of patient tinkering. “When I look at this ingredients list, I don’t see a secret,” he says. “I see judicious use of products that do what they need [to do].” So hats (halos?) off to you, Mr. Woolverton, and may the binge-watching, pint-guzzling, relatively guiltless movie marathons commence.

How to Make Diet Ice Cream That Actually Tastes Good