That’s a very interesting question, reader Charles. I don’t know the definitive answer to that, save for the fact that Native Americans were doing it well before anyone else. They were the ones who noticed that a little wood ash added to a grain cake batter created bubbles that lightened the finished product. My guess is that colonists to the New World took note of these practices and refined them to create what we now know as chemical leavening agents. These sorts of products would have been especially useful on the American frontier where, unlike back home in Europe, there were no village or estate bakeries where people could easily acquire bread. If Americans wanted bread they had to make their own — and chemical leavening was the quickest and easiest way to do that.
Americans first took to wood ash-based potash and pearlash not because they liked the taste of ashes per se, but because wood ashes were readily at hand. Indeed you might say that back in those days ashes were the one of the pillars of the American economy.
Potash as I mentioned below is critical for the manufacture of glass. Why is that? Well we all know that glass is made by melting down sand (silica) and manipulating it into various shapes. It takes a lot of heat to so that. In fact pure silica has a melting point in excess of 3500 degrees Fahrenheit. A fire that hot was very difficult to create in those days and just as importantly it was extremely dangerous to work around. But what if you could add something to the silica to lower its melting point so you don’t need as much heat? Substances that perform this function are known as a fluxes in the manufacturing world, and that’s exactly what potash was. Added to silica, it lowered its melting point by about 1700 degrees, thus creating a safer, more comfortable, less fuel-intensive working environment for glass-makers.
The trouble for England in those days was that they needed glass but had very little potash due to the fact that they’d cut down most of their trees to make ships. All that changed when the New World was discovered. North America, due to its seemingly limitless forests, became a veritable potash factory as settlers occupied tracts of land and clear-cut them to create farm fields. The old growth trees that grew there were especially rich sources of potassium carbonate. Burned for their ashes, they provided the quick cash infusion that poor immigrant farmers needed to buy seed, supplies, and building materials for their homes.
So then how is potash made? Basically by putting wood ashes into a vessel with a hole at the bottom and soaking them with water. With time the water leeches the impure potassium carbonate out of the ashes and it drips out the bottom of the vessel. This liquid is called…anyone? Anyone? Yes, you at the back with the chemical burns. That’s right: lye. Lye is a caustic alkaline liquid which itself had a variety of uses on the frontier (like making soap). Dried, however, it yielded a black crystalline powder: potash.
It took over an acre of big, old-growth trees to produce a single ton of potash, but then the early colonists weren’t really thinking about deforestation. From their vantage point the forests of North America went on forever. And oh boy were the glass makers of the Old World willing to pay for their burnt remains. No wonder that the very first U.S. patent ever issued went to a gentleman by the name of Samuel Hopkins of Philadelphia for an improved method of “making pot ash and pearl ashes.” Potash was just as important to Canada, of course, and that nation remains the world’s leading producer of potash to this day.