Acids are invaluable mainstay cooking ingredients. Lemon and lime juices, myriad vinegars and sour salt, or citric acid, can brighten and balance the flavor of almost any food. But what about their chemical opposites, the un-acids?

These are the alkalis . The only alkali that most cooks have used is baking soda. And about all we do with it is pair it with a neutralizing acid to make carbon dioxide bubbles that leaven pancakes or baked goods. It’s a mineral, like most alkalis, and it tastes bitter and soapy.

In fact there are a number of equally distasteful alkalis that still manage to create distinctively tasty foods . Even lye, an alkali strong enough to double as a drain cleaner, is now sold for making pretzels. An intriguing variety of prepared foods owe their special qualities to alkalis.

The unmistakable aroma of corn tortillas develops from the initial cooking of the corn kernels with the alkaline mineral lime. Mild cocoa powders for hot chocolate are made by treating natural cocoas with alkaline carbonate minerals. Lye is a standard ingredient for making cured olives. It also turns dried cod into the gelatinous Scandinavian oddity called lutefisk. And you can immerse eggs in a lye-salt brine for a week or two and get a version of Chinese century eggs .

Alkaline materials come in different strengths. Lye is especially strong and corrosive . A weaker group of alkalis is the carbonates, which includes baking soda. For cooking, spread a layer of soda on a foil-covered baking sheet and bake it at 120 to 150 degrees Celsius for an hour.

Baked soda is strong enough to make a good lye substitute for pretzels and is a standard ingredient in Chinese kitchens, where it’s called jian, a defining ingredient in alkaline wheat noodles. The version of Chinese alkaline noodles most familiar in the West is the Japanese ramen soup noodle.

It’s normally made with kansui, a mixture of sodium carbonate and potassium carbonate. The New York chef David Chang published a recipe in his cookbook “Momofuku.” I experimented with Mr. Chang’s recipe, and found that I could get the alkaline noodle qualities with baked soda alone.

I also found that standard bread and all-purpose flours didn’t develop much yellow color, probably because refined flours have low levels of the wheat pigments that produce it. So I tried making a dough with durum semolina, the naturally yellow coarse flour used to make dry Italian-style pastas.

The noodles came out properly yellow, slippery and full flavored. This semolina-jian mixture may sound odd, but I think of it as a happy hybrid from the planet’s preeminent noodle cultures.


HAROLD MCGEE/ESSAY