Salty Peanuts

Q: How do peanut processors get salt into roasted, salted peanuts in the shell?
--L.M.A., Sandia Park, NM

A: "The answer to your reader's question is not obvious, but simple," says Dr. Victor Sobolev, US Department of Agriculture Chemist, National Peanut Research Laboratory.

Peanut processors cook the peanuts in a briny solution under pressure for about 15 minutes. The pressure forces salt into the peanut shell. That's how the salt gets inside. Then they remove excess water by roasting them either in a dry, hot (usually 800º F) oven for 50 minutes or in oil for five.

"Roasting dramatically changes the peanut composition," says Sobolev. "[Peanut] sugars react with amino acids to form flavor compounds."

How many compounds make up that roasted flavor?

"Several hundred," says Sobolev.

(Answered October 2000; updated April 21, 2008)