TL;DR
Lye curing removes the bitterness from fresh olives in 12-24 hours (versus weeks for water curing). Nixtamalization cooks corn in alkaline solution to release niacin and improve nutritional value — this process is mandatory for corn-dependent diets and was one of the most important food discoveries in human history. Both processes are safe when handled correctly with proper dilution and rinsing.
Lye (sodium hydroxide) and calcium hydroxide (pickling lime) are caustic alkalines that cause chemical burns on contact with skin, eyes, and mucous membranes. Wear rubber gloves and eye protection whenever handling lye solutions. Never use aluminum pots or utensils with lye — the reaction produces hydrogen gas. Add lye to water, never water to lye (to prevent dangerous spattering). In case of contact: flush with large amounts of water for 15-20 minutes.
Part 1: Lye Curing Olives
Why Lye Works
Fresh olives contain oleuropein — a polyphenol that gives them their characteristic extreme bitterness. It is present in concentrations of 1-14% of olive dry weight.
Sodium hydroxide (lye) at dilute concentration hydrolyzes oleuropein rapidly, breaking it into bitter-free compounds. The process penetrates the olive from the outside in. When lye has penetrated to the pit, the olive is ready to rinse.
Alternative curing methods:
- Water curing: 4-8 weeks, daily water changes
- Salt curing: 3-12 months in brine
- Dry salt curing: 1-2 months
- Lye curing: 12-24 hours
Lye Solution Preparation
Do not use drain cleaner. Use food-grade sodium hydroxide only (available from soap-making and food processing suppliers, labeled "food grade").
Concentration: 0.5-1% NaOH solution. This is a dilute solution — much weaker than soap-making concentrations.
For 1 gallon of solution:
- 1 gallon cold water in a non-aluminum container (stainless steel, glass, food-grade plastic)
- 0.5-1 tablespoon food-grade sodium hydroxide (weigh rather than measure by volume for accuracy — 10-20 grams per gallon for 0.5-1%)
Adding lye to water: Always add lye to water, not water to lye. The reaction is exothermic (heat-generating) — stir slowly until dissolved. The solution will become warm.
Curing Process
Flavor and Seasoning
After curing and rinsing, olives are bland. Season the packing brine:
- Garlic cloves (dried for room-temperature storage, fresh for refrigerator-only storage)
- Dried herbs: oregano, thyme, rosemary
- Dried chili peppers
- Citrus peel (dried)
- Fennel seed
Part 2: Nixtamalization
The Nutritional Importance
Corn (maize) is nutritionally incomplete in raw form. The niacin (vitamin B3) in whole corn is chemically bound — human digestive enzymes cannot access it. Regular corn consumption without nixtamalization leads to pellagra, a niacin-deficiency disease that causes dementia, dermatitis, diarrhea, and death.
The indigenous peoples of Mesoamerica discovered nixtamalization approximately 3,500 years ago. When Spanish colonizers brought corn to Europe and Africa without the nixtamalization technique, pellagra epidemics followed. The disease remained mysterious until the connection to unnixtamalized corn was made in the early 20th century.
For any preparedness plan that includes corn as a significant caloric staple: nixtamalization is mandatory, not optional.
Using Calcium Hydroxide (Traditional Method)
Equipment:
- Large non-reactive pot (stainless, enamel, ceramic, glass — not aluminum)
- Food-grade calcium hydroxide (cal, pickling lime, slaked lime — available at Latin grocery stores and some hardware stores)
- Dried corn (whole kernel field corn, dent corn, or any dried corn variety)
Ratio: 1 pound dried corn : 2 tablespoons calcium hydroxide : 4-5 cups water
Using Wood Ash Water (Traditional, No-Supply Method)
For scenarios without commercial calcium hydroxide:
- Collect hardwood ash (oak, maple, hickory — clean ash without debris)
- Mix 2 cups ash with 4 cups water. Stir thoroughly.
- Allow to settle for 2-4 hours.
- Carefully strain the clear alkaline water off the settled ash. This is your nixtamalization liquid.
- pH of proper ash water should be 10-12 (if you have pH strips). More ash increases pH.
- Proceed with corn as above — simmer corn in ash water for 30-50 minutes, soak overnight, rinse well.
Wood ash water varies in alkalinity, so the process is less predictable than commercial cal, but the same underlying chemistry applies.
Making Masa from Nixtamal
Masa is the ground nixtamal dough used for tortillas, tamales, and other corn preparations.
Traditional method: Grind soaked nixtamal on a metate (flat grinding stone) with a mano (hand stone), adding small amounts of water to produce a smooth, pliable dough.
Modern method: A hand-cranked corn grinder or grain mill can process nixtamal to a usable masa. A food processor produces a usable if slightly coarser result.
Masa application: Roll between plastic sheets and press to 1/8 inch. Cook on a dry skillet over medium-high heat 45-60 seconds per side until dry and lightly toasted. The result is a corn tortilla — calorie-dense, satisfying, complete in nutrition.
Hominy (Whole Kernel, Not Ground)
If you want whole grain hominy rather than ground masa:
Continue cooking nixtamal longer — an additional 1-2 hours until the kernels are tender and puffed. Rinse thoroughly. The result is hominy — used whole in soups (posole), or dried and stored for later use.
Dried hominy stores for months in a sealed container. Rehydrate in water for 4-8 hours before cooking.
Pro Tip
Stock calcium hydroxide (pickling lime) as a preparedness supply if corn is in your long-term food storage. A 2-pound container is inexpensive and processes hundreds of pounds of corn. Without it, you have an incomplete nutrition source. With it, corn becomes the calorie backbone it was for pre-Columbian civilizations. A 50-pound sack of field corn plus the knowledge and materials to nixtamalize it is a serious emergency food foundation.
Sources
- USDA National Center for Home Food Preservation - Olives
- FAO - Traditional Maize Processing in Latin America
- Bressanin, C. - Lye Processing and Food Safety
- DiPelino, F. - The Science of Nixtamalization
Frequently Asked Questions
Is food-grade lye safe to use for food processing?
Food-grade sodium hydroxide (lye, NaOH) is safe when used correctly with proper dilution, and is FDA-approved as a food additive. The key safety requirements: use food-grade lye only (not drain cleaner which contains impurities), use proper dilution (typically 0.5-1% solution for olives), wear rubber gloves and eye protection, work in a ventilated area, and never mix lye with aluminum containers (dangerous reaction). When lye is properly rinsed from processed food, no detectable residue remains.
Why do olives need to be cured before eating?
Fresh olives contain oleuropein, an extremely bitter polyphenol that makes them inedible directly from the tree. Lye curing works in 12-24 hours by breaking down the oleuropein chemically. Water curing takes 4-8 weeks of daily water changes. Salt/brine curing takes 3-12 months. Lye is faster than any alternative method by a factor of weeks to months.
What is nixtamalization and why does it matter?
Nixtamalization is the process of cooking dried corn in an alkaline solution (traditionally wood ash water or lime water) and soaking it overnight before processing into masa (dough) or hominy. The alkaline treatment releases bound niacin (vitamin B3) that is otherwise biologically unavailable from corn, significantly improves amino acid profile, and makes the corn easier to grind. Populations that eat corn as a staple without nixtamalization develop pellagra (niacin deficiency). It is not optional for corn-dependent diets.
Can you nixtamalize corn without food-grade lime?
Yes. Traditional wood ash water (lye water made by leaching wood ash) was the original nixtamalization agent. Collect wood ash from hardwood (not softwood), add to water (1 cup ash per 2 cups water), stir, let settle for 2-4 hours, and strain the clear alkaline water. Use this ash water to cook the corn. The pH is lower and less consistent than food-grade calcium hydroxide, but it works.
What is the difference between food-grade lye and pickling lime for nixtamalization?
Food-grade calcium hydroxide (cal, pickling lime) is the traditional nixtamalization agent used throughout Latin America. Sodium hydroxide (NaOH) also works but at much lower concentrations (0.5-1% vs 1-2% for cal). Calcium hydroxide is gentler and more forgiving, adds calcium to the final product, and is the preferred choice for nixtamalization. Sodium hydroxide works but is harsher and less traditional.