Potash: The Ashes That Raised a Nation

Potash: The Ashes That Raised a Nation

Long before baking powder revolutionized home kitchens, early American bakers demonstrated their ingenuity by using potash—an alkaline residue from wood ash—as a leavening agent. Extracted from hearth ashes, potash enabled cooks to prepare lighter breads and cakes, showcasing their resourcefulness before the advent of commercial yeast or baking soda.

This article builds on our previous piece ‘From Ashes to Antlers’ , which explored the historical use of various natural materials in early American kitchens. Let's take a closer look at potash's role in early American kitchens.

What Is Potash?

Early American cooks made potash (potassium carbonate) by soaking hardwood ashes in water to create lye, then boiling the liquid until it yielded a solid alkaline salt. The name "potash" comes from this process of boiling ashes in pots.

Lye Safety and Myths

• Is lye dangerous? In concentrated form, yes. Historical potash lye was milder but still required care.
• Safe to eat? Yes, when neutralized adequately with acid. The reaction produces water and carbon dioxide.
• Make it today? It's possible, but use gloves and eye protection.
• Myth: "Lye is poison." → Truth: It was a standard kitchen tool for soap, pretzels, and baking.

The Chemistry of Potash Leavening

Potash requires an acid (such as molasses or sour milk) to create carbon dioxide, which helps lift the dough. This simple reaction laid the foundation for early quick breads.

• Source: Hardwood ash
• Type: Potassium carbonate
• Reaction: Potash + Acid → CO₂ → Rise

What Is Pearl Ash?

Pearl ash is refined potash. Makers dissolved potash in water, filtered it, and evaporated the solution to create a whiter, cleaner salt ideal for baking delicate cakes.

• Potash: Crude wood ash residue
• Pearl Ash: Refined, purified potash
• Used in: Gingerbread, sponge cake, biscuits

Historic Use in Recipes

Amelia Simmons’ American Cookery (1796) frequently used pearl ash with acidic ingredients. Below is a modern version of her gingerbread recipe.

Gingerbread with Pearl Ash

• 1 cup molasses
• 1/2 cup sour cream or buttermilk
• 1 tsp pearl ash (or baking soda)
• 1 tbsp ground ginger
• 2.5–3 cups flour

Instructions: Mix pearl ash with sour cream. Stir in molasses and ginger. Add flour gradually. Bake at 350°F for 20–25 minutes.

Other Recipes Using Potash

Beyond gingerbread, early American bakers showcased the versatility of potash in a variety of recipes where mild sweetness and dense structure were welcome. Typical dishes included molasses cakes, Johnnycakes (cornmeal flatbreads), spice biscuits, and hoecakes. These recipes often relied on potash for rise when eggs were scarce or sour milk was abundant. Amelia Simmons and other early cookbooks also mention "loaf cakes" and "crackers" leavened with potash or pearl ash, highlighting its wide range of uses.

From Hearth to Pantry: How Baking Powder Changed Everything

The introduction of baking powder in the mid-19th century marked a significant turning point in the history of baking. Potash-leavened goods tend to have a slightly soapy or alkaline note if not carefully balanced with acid. The texture was often denser, with a subtle chewiness, especially in quick breads and cakes. Baking powder, by contrast, offered a more neutral flavor and consistently resulted in a lighter crumb. It allowed bakers to move away from strong molasses and buttermilk flavors used to balance potash, resulting in the sweeter, fluffier cakes familiar today.

Regional Variations in Potash Use

The use of potash varied across the colonies. In the Northeast and Appalachian regions, where hardwood forests were abundant and molasses was a common sweetener, potash remained in use longer—especially among rural homesteads. In German- and Dutch-influenced areas like Pennsylvania, cooks developed refined versions of traditional baked goods (such as honey cakes and lebkuchen) using pearl ash. Southern cooks were more likely to switch earlier to baking soda and sour milk once commercial supply chains improved.

Comparison of Leaveners

Leavener	Source	Needs Acid?	Use	Flavor	Consistency
Potash	Wood ash	Yes	Breads	Alkaline	Unrefined
Pearl Ash	Refined potash	Yes	Cakes	Mild	Reliable
Baking Powder	Commercial blend	No	All baking	Neutral	Very consistent

Griddle Cakes Before Johnnycakes: A Historical Comparison

Medieval Flat Cakes (14th–15th c.)

Source: Le Ménagier de Paris (1393)
Typical Ingredients: Wheat flour, milk or water, egg (optional)
Cooking Method: Griddled on a flat iron, stone, or in a pan with fat

“Make a paste with white flour and warm water... roll thin and bake on the iron.”

These cakes were simple and unleavened, sometimes brushed with fat or sprinkled with sugar. Texture would be dense and chewy. A modern interpretation uses wheat flour and warm water to form a thick dough, rolled or patted thin, then cooked on a dry or greased skillet.

Early Modern Pancakes (16th c.)

Source: A Proper Newe Booke of Cokerye (c. 1557)
Typical Ingredients: White flour, eggs, milk or ale/wine, spices
Cooking Method: Fried on a griddle or pan with butter/lard

“To make pancakes. Take two or three eggs, a dish of flour, and half a pint of milk. Beat them together and fry them in butter.”

These pancakes were thinner, lighter, and crispier—thanks to the addition of eggs and sometimes alcohol. A modern version might whisk 2 eggs, 1 cup flour, and ½ cup ale or milk, then fry in a buttered pan until golden.

Colonial Johnnycakes (17th–18th c.)

Source: Indigenous North American cooking, adapted by colonists
Typical Ingredients: Cornmeal, water or milk, salt, fat or molasses
Optional Leavening: Potash or pearl ash
Cooking Method: Griddled, stone-baked, or pan-fried

“Indian meal, scalded, mixed with salt, milk, or cream, and baked on a griddle or board.” — Amelia Simmons, 1796

Colonial johnnycakes often used hot water to soften cornmeal, sometimes with milk or sweeteners. When leavened with potash, they developed a slightly fluffy interior with a crisp outer crust.

Summary: Griddle Cake Evolution

Period	Dish	Grain Base	Leavening	Fat Used	Texture	Region
14th c.	Iron cakes / wafers	Wheat	None	None or lard	Dense, flat	France, England
16th c.	Pancakes	Wheat	Eggs	Butter/lard	Thin, crisp	England
17th–18th c.	Johnnycakes	Cornmeal	None or potash	Drippings or none	Crisp outside, tender inside	Colonial America

Timeline of Leavening

• Pre-1600s: Natural fermentation
• 1600s–1700s: Potash use in breads
• 1796: Pearl ash in American Cookery
• 1830s: Hartshorn for cookies
• 1850s: Commercial baking powders introduced
• 1880s+: Double-acting powders dominate

Where to Find Historical Leaveners Today

If you're interested in experimenting with historic recipes, you can still obtain several early leavening agents with care. Be sure to use only food-grade versions, and always follow recipes that include appropriate acidic ingredients when working with alkaline leaveners like potash or pearl ash.

Reputable Sources

• Pearl Ash (Food-grade Potassium Carbonate):
  - Lehman's: Carries pearl ash suitable for reenactment or heritage baking
  - Amazon: Search for “potassium carbonate, food-grade” (check vendor reviews)
• Hartshorn (Ammonium Carbonate):
  - King Arthur Baking: Sold as “Baker’s Ammonia”
  - Amazon: Look for “Baker’s Ammonia” or “Hartshorn” (food-grade only)
• Potash (Historical or DIY):
  - True culinary-grade historical potash is rare. For educational or reenactment use, you can try making it at home from hardwood ashes.
  - Permies Forum Guide: Practical advice on making your own potash safely

⚠️ Note: Commercial potash sold for fertilizer or soapmaking is not food-safe. Always verify the product is labeled for culinary use before baking.

To explore more, read From Ashes to Antlers.

More Forgotten Leaveners

Discover hartshorn and other historic techniques in our full guide.

Browse all leavening articles here.

Potash & Pearl Ash: The Alkaline Origins of American Baking

Front cover and title page scans from Amelia Simmons’s American Cookery (1796)

From Ash to Rise: Potash, Pearl Ash, and the First American Chemical Leaveners

Before commercial baking powder revolutionized the kitchen, early bakers reached for something far more rustic: ashes. Specifically, they utilized the lye-rich remnants of burned hardwood to produce potash and, later, its refined cousin, pearl ash. These alkaline salts, when combined with acidic ingredients, acted as the first chemical leaveners of early American and European baking.

What is Potash?

Potash, or potassium carbonate, is derived from the ashes of burned hardwood. Traditionally, early cooks would soak wood ash in water, extract the resulting lye, and boil off the liquid to concentrate the alkaline residue.  The name "pot ash" originates from the iron pots historically used during this production process. 

Pearl Ash: The Cleaner Leavener

Pearl ash is a purified form of potash.  The refinement process involved dissolving crude potash in water, allowing the insoluble sediment to settle, then filtering and gently evaporating the solution until white crystals formed. This process created a cleaner, more consistent leavening agent preferred for baking cakes and biscuits.

How Alkaline Leavening Works

Neither potash nor pearl ash works alone. They need an acidic partner to trigger a chemical reaction that produces carbon dioxide gas. This gas forms bubbles in batters and doughs, helping them rise and achieve a light texture. 

• Potash: Stronger, more caustic, less refined — best used with caution or in soapmaking.
• Pearl Ash: More purified, milder, and food safe —  suitable for cakes, biscuits, and cookies.

How Does It Compare to Hartshorn?

Hartshorn, or ammonium carbonate, differs in that it does not require an acid to activate.  It's ideal for crisp cookies like Springerle, where dryness is key.  In contrast, potash-based leaveners must be carefully balanced with acidic components, or the resulting bake may carry an unpleasant alkaline flavor.  Potash typically found its place in softer quick breads and early cakes. 

📚 Curious about hartshorn? Click here to explore how bakers used ammonium carbonate before baking soda became common.

Refining Potash into Pearl Ash

Pearl ash isn’t just cleaner potash—it’s the result of a deliberate purification process. Historically, makers dissolved crude potash in water, allowed insoluble impurities to settle out, then filtered and gently evaporated the liquid until white crystals formed. This recrystallized form offered better predictability and reduced off-flavors in baked goods.

Common Acidic Pairings in Historical Recipes

• Buttermilk or clabbered milk
• Molasses (commonly used in gingerbreads)
• Vinegar or sour wine
• Apple cider or citrus juice

Historical Note: Gingerbread with Pearl Ash

The earliest American-published cookbook, American Cookery by Amelia Simmons (1796), includes several recipes calling for pearl ash as a leavening agent. One gingerbread variant reads:

“Gingerbread Cakes” – One quart of molasses, one pound of sugar, three quarters of a pound of shortening, one cup of sour milk, four teaspoons pearl ash, four tablespoons ginger, cinnamon and cloves to taste, and as much flour as will make it roll out.

— Amelia Simmons, American Cookery (1796)

Where to Find Potash or Pearl Ash Today

• Potash: You can make it at home from hardwood ashes, but for safety and consistency, it's best sourced as food-grade potassium carbonate from specialty chemical suppliers or soapmaking shops (e.g., Bulk Apothecary, The Lye Guy).
• Pearl Ash: Much harder to find today, but chemically similar results can be achieved with food-grade potassium carbonate or by using baking soda (sodium bicarbonate) in a modern adaptation.

Example: Gingerbread with Pearl Ash (1796)

Amelia Simmons’s American Cookery (1796) features several gingerbread cookie recipes that call for pearl ash—a purified form of potash—dissolved in milk or water. This marks one of the earliest printed uses of a chemical leavener in American baking. 🧁

View the original 1796 scans, or check the Smithsonian & American Heritage notes on Simmons's innovations :contentReference[oaicite:2]{index=2}.

Historical Example: Gingerbread with Pearl Ash

Adapted from late 18th-century sources:

• 2 cups flour
• 1 cup molasses
• 1/4 cup butter, melted
• 1 tsp pearl ash dissolved in 1 tbsp vinegar
• 1 tsp ginger
• 1/2 tsp cinnamon
• Optional: cloves or nutmeg

1. Mix molasses, butter, and spices.
2. Add pearl ash mixture.
3. Stir in flour gradually to form a dough.
4. Drop by spoonful or roll and cut into rounds.
5. Bake at 350°F for 10–12 minutes.

📜 Want to learn more about potash and pearl ash? Click here to explore how ashes became America’s first chemical leaveners.

The Rise of Baking Powder

The arrival of commercial baking powder made baking more accessible. Unlike potash or pearl ash, it included both alkaline and acidic components, eliminating the guesswork. Home cooks no longer needed to rely on tricky ratios or worry about acidic pairings—baking became easier, faster, and more reliable. This convenience marked the end of Pearl Ash’s reign in the kitchen.

Other Forgotten Leaveners

Before modern yeast and chemical leaveners, a variety of traditional techniques helped baked goods to rise 

• Ale barm: Foam from fermenting beer, used in breads and cakes before commercial yeast.
• Egg leavening: Beaten egg whites or whole eggs incorporated air, helping cakes and sponges rise naturally.
• Sack starters: Fermented mixtures using sack (fortified wine) and flour as makeshift yeast.

Quick Comparison: Forgotten Alkaline Leaveners

Leavener	Source	Needs Acid?	Best Used In
Potash	Boiled wood ash	Yes	Quick breads, early cakes
Pearl Ash	Purified potash	Yes	Gingerbread, sponge cake
Hartshorn	Distilled antlers or hooves	No	Crisp cookies, Springerle

Further Reading & Recipes to Explore

• Hartshorn in Historical Cookies
• Wikipedia: Potash
• Wikipedia: Pearl Ash
• Amelia Simmons’ American Cookery (1796)

🧾 Coming Soon: This post is part of the Forgotten Leaveners series. Watch for the downloadable bundle, including:

• Comparison chart of early leaveners
• Printable recipe cards
• Bonus bakes: potash cakes, Springerle, and more

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