Why does frozen custard taste so much different than soft-serve ice cream? —Willie W., St. Louis

Let me start by saying that all custard is soft-serve, but the converse is not true. The main difference comes down to one ingredient: eggs.

Ice cream is made from milk, cream (or a combination of the two), and sugar. Frozen custard adds egg yolks (no less than 1.4 percent egg yolk solids by weight, per FDA guidelines). If the product contains less than that, it’s considered ice cream. Because soft-serve isn’t packaged or frozen, there are no FDA standards for it, but most people still consider it to be “ice cream” (which, to be technical, contains more milk fat). Regardless, there are two other differences between soft-serve ice cream and custard:

1. Air. Commonly called overrun, the volume of air introduced (from 0 to 100 percent) alters the taste of the finished product. Soft-serve typically contains 35-45 percent overrun (producing a softer, fluffier, whiter product), while that for custard is 15-30 percent (which results in a heavier, creamier, more dense product).

2. The machine. Soft-serve machines constantly churn air into the product to achieve the desired light consistency and mouthfeel; custard machines introduce far less air, as noted above. Soft-serve is dispensed to order via a pull handle and can be fashioned into squiggles and peaks. Custard machines are typically far more expensive than soft-serve machines (top-of-the-line Taylor freezers cost upwards of $75,000) and use a continuous-feed system that directs a much firmer product down a stainless-steel chute and into a holding vessel. To maintain consistency, custard’s normally served within minutes after production. (There are places in St. Louis that use soft-serve machines to dispense custard, which to me is gaming the system. Taste batch-made custard and soft serve “custard” side by side, and the difference is astounding. But I digress…)

Proper frozen custard should be made fresh and served immediately. The places that sell take-home containers of rock-hard product have short-changed themselves. I’ve never understood why anyone would want to take a product’s biggest selling point—in custard’s case, the creamy consistency and luxurious texture—and turn that, well, upside down. At that point, you’re just another freezer-case product; quite frankly, there are a lot better versions of those out there, among them Graeter’s, Häagen-Dazs, Jeni’s, and local makers Clementine’s, Jilly’s, and Serendipity.

So where should you go for worthy frozen custard in St. Louis? Aside from local institution Ted Drewes, which needs no introduction or hype (especially after Dateline’s visit and subsequent video last fall), here’s a small serving of my personal faves:

Andy’s Frozen Custard (three metro locations): With more than 50 locations in 10 states, Andy’s claims to be the largest dessert-only franchise in the world. Setting Andy’s apart are the seasonal add-ins (fresh strawberries, blueberries, blackberries, peaches, plus apple, pumpkin, and Key Lime Pie) and “Jackhammer” concretes, which boast a topping-filled core.

Bobby’s Frozen Custard: Known for its Sunday-night summer concerts and located in Maryville, Illinois (population 7,900), the small-town vibe is genuine. The custard cakes, Bobby’s Turtle Pie, and seasonal caramel apples are welcome additions.

Fritz’s Frozen Custard (five metro locations): Besides several versions of vanilla and chocolate custard, Fritz’s has featured a flavor of the day since 1985. (See the September calendar here.)

Silky’s Frozen Custard (three area locations): SLM dining writers Pat Eby and Dave Lowry have both waxed poetic about Silky’s, and I don’t disagree. Although there’s no need to stray from the specialties (Turtle, Elvis Pretzely, Muddy Sneakers, etc.), a handheld custard cookie sandwich (vanilla, chocolate, mint, and a flavor of the day) is a pleasant diversion.

Shake Shack: Coming later this year to the Central West End, ex-pat Danny Meyer’s legendary chain of burger and custard joints was inspired by the likes of Steak n Shake and Ted Drewes.

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