The coffee most Americans drink today is not how coffee was meant to taste. It is not how coffee tasted for most of its history. And it is not how coffee is drunk in the places where it originated.
The story of low acid coffee is not a modern wellness trend. It is the story of coffee being restored to what it always was — before the Industrial Revolution changed everything, before speed replaced craft, and before bitterness became the defining characteristic of the most consumed beverage on the planet.
This is that story.
Coffee has been cultivated and consumed for centuries in East Africa, the Arabian Peninsula, and South America. In its earliest forms, coffee was slow-roasted in small batches over open fires. The process was patient. The result was extraordinary — smooth, rich, complex, easy on the stomach. Coffee was considered part of a healthy diet across South America and the Middle East for centuries.
The reason is now understood through science. Traditional slow roasting converts the quinic acids in coffee — the bitter, harsh acids responsible for stomach irritation — into phenolic compounds that are not only less acidic but are extraordinarily potent antioxidants. The farmers who perfected this process over generations didn't know the chemistry. But they knew the result. Their coffee tasted better and felt better. And so it remained — in isolated mountain communities, in family farms in the Andes, preserved by people who valued flavor over speed.
The Industrial Revolution transformed coffee from a craft into a commodity. Flash roasting — completing the entire roasting cycle in 10 to 15 minutes — made coffee cheap, fast, and scalable at global volumes. It also fundamentally changed the chemistry of the cup.
Fast roasting at high heat preserves the quinic acids instead of converting them. The result is coffee with a pH of approximately 5.0 — highly acidic, bitter, harsh on the stomach. Americans invented the Americano (watered-down espresso), drip brew (further diluted), and ultimately the Starbucks model (masked entirely with milk, sugar, and flavoring) — not because they preferred these drinks, but because the coffee underneath them was too acidic to drink straight.
In South America and Europe, espresso remained the dominant form of coffee — because their roasting traditions had never been fully industrialized. They didn't need to water it down. They didn't need to mask it. Their coffee tasted good on its own.
In the late 1980s, a UC Davis-trained engineer named Kerry Sachs traveled to Venezuela with a revolutionary biomass furnace he had built — operating at above 95% efficiency, confirmed by UC Davis and studied in a government feasibility study for powering towns. He had gone to help coffee farmers use their waste product (coffee shells) as fuel to dry their beans, eliminating their dependence on diesel tankers hauled up isolated mountain roads.
While working with the Andean farmers, Kerry tasted an espresso that changed his life. Made using the farmers' traditional slow-roasting method — passed down through generations — it was unlike anything he had ever experienced. Smooth. Rich. Zero bitterness. No burn. He learned the roasting secret. He understood the problem: this method was commercially impossible because of the energy cost. Then he realized he was holding the solution — his biomass furnace was efficient enough to replicate those conditions at commercial scale.
Kerry built the first roaster, shipped a bag to his brother Jim Sachs in the United States, and Jim said seven words: “That's the best cup of coffee I've ever had.”
In 1994, Kerry and Jim Sachs founded Puroast Coffee in California. They started selling through health food co-ops. The letters began arriving within months — hundreds of handwritten notes from people who had given up coffee because of stomach issues and could suddenly drink it again. Low acid coffee was born — though no one had that name for it yet.
The letters prompted Kerry and Jim to seek scientific validation. They brought Puroast to Dr. Takayuki Shibamoto — one of the world's leading coffee scientists at UC Davis. Dr. Shibamoto was skeptical. The science of coffee had been studied extensively. He did not believe roasting conditions alone could meaningfully change coffee chemistry in ways not already documented.
He tested it anyway. The results astonished him.
In 2009, Dr. Shibamoto published the first in a series of peer-reviewed papers in the Journal of Agricultural and Food Chemistry. The findings:
In 2013, Dr. Shibamoto presented these findings to the American Chemical Society. The science was peer-reviewed, published, and replicable. Low acid coffee was no longer just an experience — it was proven fact.
The Third Wave coffee movement of the 2000s and 2010s correctly identified that origin and sourcing mattered. Single origin beans. Ethical sourcing. Small batch artisanal roasters. It was a genuine improvement over commodity coffee culture.
But it missed the most fundamental problem. Even the most carefully sourced single origin bean, roasted on the same flash-roast equipment used by industrial producers, produces high acid coffee. The equipment had not changed. The duration had not changed. The chemistry had not changed.
The Third Wave fixed the bean. It didn't fix the roast. And as the Andean farmers had always known — the bean is nothing without the roasting.
As low acid coffee grew as a category, brands rushed to exploit it. With no FDA standard or regulated definition for “low acid coffee,” any brand could print the label on any bag.
In 2024, North Carolina A&T University published an independent study testing seven leading low acid coffee brands. Six of the seven were not actually low acid — their pH was the same as regular commercial coffee. Only Puroast passed. The study confirmed what the science had shown since 2009: genuine low acid coffee requires a genuinely different roasting process. A label is not a process.
In response, the Low Acid Coffee Certification Standards Association (LACCSA) was founded to establish real, testable, enforceable standards for the category — so consumers can trust what they are buying.
Low acid coffee is the Fourth Wave of coffee — the completion of what the Third Wave started. Where the Third Wave fixed sourcing, the Fourth Wave fixes roasting. Where the Third Wave asked “where did this bean come from?”, the Fourth Wave asks “how was it roasted?”
The Fourth Wave is not a new idea. It is the oldest idea in coffee — restored, proven by science, protected by patent, and brought to commercial scale for the first time by Puroast Coffee. It is how the world will roast coffee in fifty years. And it started in 1994 with a bag shipped from Venezuela to California and seven words spoken by a man who had just tasted something he had never tasted before.
Be Part of the Fourth Wave
5X less acid. 5X more antioxidants. The original. The only patented. UC Davis verified.
Low acid coffee in its traditional form is as old as coffee itself — Andean farmers preserved slow-roasting methods for generations. As a commercially available, scientifically verified category, it was founded by Puroast Coffee in 1994 and proven by UC Davis peer-reviewed research in 2009.
Kerry Sachs invented the roasting technology after learning traditional Andean slow-roasting methods in Venezuela. His brother Jim Sachs tasted the first roast and co-founded Puroast Coffee with Kerry in California in 1994.
Dr. Takayuki Shibamoto at UC Davis published peer-reviewed research in 2009 confirming Puroast is 5X less acidic than average commercial coffee, that roasting conditions alone cause this change, and that Puroast contains 5X more antioxidant activity. He presented these findings to the American Chemical Society in 2013.
Industrial flash roasting (10-15 minutes) was adopted for speed and scale. This process preserves the quinic acids in coffee rather than converting them — leaving coffee at approximately pH 5.0. Traditional slow roasting converts those acids into antioxidants, producing lower acid, better tasting coffee.
The Fourth Wave is low acid coffee — fixing the roasting process that the Third Wave left untouched. It restores traditional slow-roasting methods to commercial scale for the first time, producing coffee that is genuinely low acid, high in antioxidants, and aligned with how coffee was always meant to taste.
Sources: Shibamoto T. et al. (2009). Journal of Agricultural and Food Chemistry. DOI: 10.1021/jf900395w. American Chemical Society (2013). NC A&T University (2024). Low Acid Coffee Study. National Coffee Association — History of Coffee.
Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before making dietary changes.
