Chapter 5: The Letters That Changed Everything — How Customer Stories Led Puroast to UC Davis

Hundreds of Letters. All Saying the Same Thing.

In Chapter 4, Kerry and Jim Sachs founded Puroast in 1994 and began selling into California co-ops. The coffee was extraordinary. People noticed. But nobody was prepared for what happened next.

Letters started arriving in the mail. This was before email — handwritten and typed letters, sent by real people who had taken the time to find an address and put a stamp on an envelope. And they all said the same thing:

Hundreds of them. All saying the same thing. People who had been told by doctors to give up coffee. People who had lived with acid reflux, GERD, stomach pain, and digestive distress for years — and had accepted that coffee was simply not for them anymore. And now, with Puroast, they were drinking coffee again. And feeling fine.

More Than Flavor — Something Else Was Happening

Kerry and Jim read every letter. And what they saw was not just satisfaction with taste. People were describing a physical difference. A bodily response that was fundamentally unlike anything they had experienced with other coffees. They felt better. Their stomachs didn't hurt. The acid burn that had driven them away from coffee was simply absent.

This was not a marketing claim. This was not a placebo. These were hundreds of independent people, with no connection to each other, all arriving at the same conclusion independently: Puroast coffee was different in a way that mattered for their health.

The Question That Sent Them Back to UC Davis

Kerry and Jim knew they had to understand what was happening scientifically. This wasn't about marketing — it was about truth. If Puroast was genuinely different in a measurable, physiological way, they needed to know why. And they needed proof that could stand up to scrutiny.

They brought the coffee back to UC Davis — the same institution that had confirmed Kerry's biomass furnace efficiency years earlier. And there they found Dr. Takayuki Shibamoto, one of the most respected coffee scientists in the world.

Dr. Shibamoto was not impressed. He was skeptical. The science of coffee had already been studied thoroughly. Roasting conditions had been examined. The chemistry was settled. If Puroast was producing different results, it was almost certainly a placebo effect. He had seen marketing claims before.

But out of scientific curiosity — and perhaps a small measure of doubt — he agreed to test it.

What he found astonished him. And the story of those results — published in 2009, presented to the American Chemical Society in 2013 — is the subject of Chapter 7.

Why the Letters Still Matter Today

The letters from those early Puroast customers were more than testimonials. They were the first signal that something scientifically significant was happening inside the cup. They were the human data that preceded the laboratory data. And they told a story that the science would eventually confirm in full.

Today, Puroast continues to receive messages — now emails, social posts, and reviews — that echo those original letters almost word for word. People with acid reflux. People with GERD. People who were told they could never drink coffee again. Finding their way back to the morning ritual they thought was lost.

That is what the letters meant. And that is what Puroast still stands for.

Continue the Story

Sources: Shibamoto, T. et al. (2009). "Antioxidant activities of coffee." Journal of Agricultural and Food Chemistry. | Shibamoto, T. (2013). American Chemical Society Presentation. | NC A&T State University (2024). Low Acid Coffee Label Study. | Puroast Company Archives.

Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional for any health concerns.

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