How does air affect the quality of ice cream?
When you churn ice cream, you’re also putting air into it, which is called overrun. If you looked at ice cream with an electron microscope, the structure would look something like a bunch of balloons, all touching each other, with a mixture of the cream, sugar, fat, protein, and ice crystals around each balloon. So air is a necessary ingredient to build the body and texture. A high overrun also creates volume, so you can have a bigger scoop that costs less. At the bottom of the ice cream freezer, you see the big plastic tubs that are inexpensive and great for families. They probably have the lowest fat, the highest sugar, and highest overrun possible. But overrun isn’t necessarily correlated with quality. Gelato, for example, can also have air in it. Quality has to do with following best practices and using special ingredients.
What’s important to you when you develop an ice cream?
I’m thinking about trying to create an experience that someone’s going to enjoy and want to repeat. I think about color, flavor, texture, sweetness, saltiness, and fattiness. It’s not uncommon when I’m building a new ice cream to make up to 40 versions. The versions might include something chunky, a ribbon of caramel, a layer of ganache on top, even a gumball at the bottom. There are a lot of variables you can try to come up with something original.
How does that get you to something from out of left field, like, say, pear and blue cheese?
My husband worked at a local dairy and sometimes he’d bring home a five-pound bag of blue cheese crumbles. I had a bag in my freezer, but it never really freezes. It just gets kind of soft and yummy, so I just knew this would be really good in ice cream. Then I thought about a charcuterie board with pear and blue cheese. I was like, ooh, we need pear and blue cheese ice cream! People go crazy over it.
You also work as a dairy judge. How would you recommend someone at home to judge ice creams?
Buy one of those big fat tubs of plain vanilla, another vanilla that’s at a mid-range price, and then one that’s made locally or where they’re talking about how they’re using the best vanilla in the world. Also buy some Häagen-Dazs. It has only five or six ingredients, and they are more like the ones you’d use if you were making ice cream at home (though Häagen-Dazs certainly has its own special equipment and processes).
Get a bunch of plates, preferably all the same color, so you can compare the colors of the different ice cream samples. Put a scoop in the center of each plate. Then let them sit for 10 or 20 minutes and see what happens. On high-overrun ice creams, the scoop will sort of retain its shape, but you’ll see a pool of liquid and foam coming off because instead of having fat create stability, the manufacturers add things like guar gum or carrageenan. For low-overrun ice creams, which tend to be more expensive, it should melt in a different way, sort of milkily, without separating liquid and foam.