But Hank, shouldn't you use "food grade" lye? Well, after much research, I can find no hard evidence—none—that says there is any difference between so-called "food grade" lye and non-food grade lye. So, you can order the food grade stuff through that link above, or go to the hardware store and use a 100-percent sodium hydroxide drain cleaner. Both will work.
Isn't lye a deadly poison? Sorta. Sodium hydroxide is one of the nastiest bases we know of; a base is the opposite of an acid. On the pH scale, distilled water is the median, at 7. Your stomach acid's pH is about 1.5—enough to burn a hole through a rug. Lye's pH is 13.
Bottom line: Raw, pure lye will burn the hell out of you, but it is not a systemic poison. That means that even if you eat an olive that still has a lot of lye in it—as I did—all you will taste is a nasty soapy flavor. If you eat a bunch of them, the alkaline pH in the olives will counteract your stomach acid and it might give you indigestion. That's all, and that's a worst-case scenario. That said, you need to be damn careful at that one moment you are moving raw, pure lye from the container to the crock you are curing into.
NEXT: A step-by-step method for lye-cured olives
Lye Curing, Step by Step
Follow these instructions and you will be fine:
• Wear glasses if you have them. Wear long sleeves and pants and closed shoes. You will probably not get lye on you, but better to be safe.
• Pour one gallon of cold—not tepid, not hot, but cold—water into a stoneware crock, a glass container, a stainless-steel pot, or a food-grade plastic pail. Under no circumstances should you use aluminum, which will react with the lye and make your olives poisonous.
• Using a measuring device that is not aluminum, add three tablespoons of lye to the water. Always add lye to water, not water to lye. A splash of unmixed lye can burn you. Stir well with a wooden spoon.
You're done. You use cold water because the reaction between lye and water generates heat, and the hotter the lye-water solution, the softer the olives will become. Now that it is mixed, the lye solution can't really hurt you, so go ahead and add your olives.
Stir them in with that wooden spoon and put something over all the olives so they do not float. This is vital. Olives exposed to air while curing turn black. Don't worry, they will absorb the water and sink in a few hours, but to start you need to submerge them.
Let this sit at room temperature for 12 hours. The alkaline solution will be seeping into the olives, breaking the bonds of the bitter oleuropein molecules, which then exit the olive and go into the water. After 12 hours, pour off the solution into the sink. It should be pretty dark in color.
Quickly resubmerge your olives in cold water. You want to minimize the exposure to air. You now have cured olives. I know, I know, a lot of recipes say to repeat the lye process another time—sometimes three more times—but that will destroy a lot of flavor; there are a ton of water-soluble flavor compounds in an olive that the lye solution washes away. Trust me. Your olives, unless they are gigantic, will not be overly bitter even after just a light, 12-hour lye soak.