Lye

A lye is a liquid metal hydroxide obtained by leaching ashes (containing largely potassium carbonate or "potash"), or a strong alkali which is highly soluble in water producing caustic basic solutions. "Lye" is commonly an alternative name of sodium hydroxide (NaOH) or historically potassium hydroxide (KOH), though the term "lye" refers to any member of a broad range of metal hydroxides.

Today, lye is commercially manufactured using a membrane cell chloralkali process. It is one of the highest-volume industrial chemicals with worldwide annual production of 45 million tons in 1998. It is supplied in various forms such as flakes, pellets, microbeads, coarse powder or a solution.

Lyes are used to cure many types of food, including the traditional Nordic lutefisk, olives (making them less bitter), canned mandarin oranges, hominy, lye rolls, century eggs, and pretzels. They are also used as a tenderizer in the crust of baked Cantonese moon cakes, in "zongzi" (glutinous rice dumplings wrapped in bamboo leaves), in chewy southern Chinese noodles popular in Hong Kong and southern China, and in Japanese ramen noodles.They are also used in kutsinta, a type of rice cake from the Philippines.

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