Making German lye-dipped pretzels—the kind with gorgeous, smooth mahogany exteriors and chewy, pleasantly dense interiors all sprinkled with pretzel salt and served with good butter—is risky business.
Science
Live Dangerously. Make Pretzels.
The smooth mahogany exterior and pleasantly dense chew of a German lye-dipped pretzel is well worth breaking out the safety goggles.
By and
Published Oct. 12, 2023.
OK, maybe that’s a bit of an exaggeration. You don’t need a full hazmat suit to make pretzels. You do, however, need a highly caustic substance. Lye in solution tops out the pH scale at 14: So alkaline, it’s used to clean drains.
So why on earth use it on food?
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How Alkalis Make Foods More Delicious
Extreme alkalis may be dangerous: But they can also transform food.
Treating dried corn with cal, or calcium hydroxide, an ancient process called as nixtamalization, is the foundation of masa, the dough that gives us tortillas, tamales, and so much more. The calcium hydroxide initiates many flavor and nutritional changes in the corn.
China’s thousand-year eggs are created using various strong alkalis. The transformation is dramatic, as the egg white turns almost black and the yolk takes on a deep green color. The flavor is incredibly rich and complex.
Even some olives are processed using lye, which works very quickly compared to the salt brine technique. It also allows the olives to retain their natural green color.
So what does lye do for a pretzel? Quite a lot. Dipping the dough in a lye solution gives traditional German pretzels their characteristic salinity, chew, and that smooth mahogany exterior. It boosts flavorful browning by accelerating Maillardization and by caramelizing sugars in the dough. And it gels surface starch so that the pretzels bake up smooth and shiny.
But most fascinating of all is that lye actually completely changes pretzel aroma. It imparts that unique pretzel smell and taste by inhibiting the creation of typical baked-good aroma compounds while spurring the formation of others. That’s why pretzels don’t smell like baked bread or anything else. They’re a singular, original treat.
Using Food-Grade Lye to Make German Pretzels
Making pretzels at home is a project, and you’ll need to read through Deputy Editor Andrea Geary’s full recipe and our guide to working with lye safely before you begin.
You’ll start by making a simple dough out of flour, yeast, salt, water, and butter. After waiting for it to rise and then dividing it into balls, you’ll roll the balls into ropes, give them a twist, and chill them in the refrigerator.
After a couple of hours, it’s time for the lye dip. Want to see it in action? Check out the latest episode of What’s Eating Dan? below.