Mycotoxins in Coffee: A Roaster's Guide to the Facts vs. the Hype

The Mycotoxin Debate: Health Concern or Marketing Hype?

Over the last year, we've seen a sharp increase in customers asking about mycotoxins in coffee. If you're one of them, you're likely focused on making the healthiest choices for your body, and that's a great thing.

However, this growing awareness has also created an opportunity for savvy marketers to label their coffee as "low-mycotoxin" or "mycotoxin-free" and attach a super-premium price tag.

As a coffee roaster with decades of experience in the industry, I believe in transparency. I dislike seeing consumers misled by fads or scare tactics. So, let's cut through the noise and look at the practical realities of mycotoxins in the coffee supply chain.

Disclaimer: I am an engineer and a coffee industry professional, not a doctor or chemist. This article is intended to balance scientific theory with the practical realities of a global agricultural industry.

What Are Mycotoxins in Coffee?

Mycotoxins are toxic compounds produced by certain types of mould or fungi. They can form on various food crops, including grains, nuts, and, yes, coffee beans, particularly during drying and storage if conditions are not ideal. The specific type most relevant to coffee is Ochratoxin A (OTA).

While the health effects of high levels of mycotoxins sound alarming, it’s crucial to view the issue with balance and perspective. These compounds exist in trace amounts in many common foods. The key is understanding how they are managed and minimized in a quality-focused supply chain.

Debunking Common "Low-Mycotoxin" Coffee Advice

Many health websites offer guides on choosing a low-mycotoxin coffee. Unfortunately, much of this advice is overly simplistic, idealistic, and often factually incorrect. Let's examine the most common claims.

Claim 1: "Only drink wet-processed (washed) coffee."

• The Theory: Mycotoxins can form during the drying phase, so washing the coffee cherry pulp off the bean first (wet-processing) is supposedly safer than letting it dry on the bean (dry-processing).

• The Reality: This is misleading. One method is not inherently safer than the other. The critical factor is the care and attention applied by the farmer or processing station. A poorly managed wet-processing facility with contaminated water or improper drying techniques can be just as risky, if not more so, than a well-managed dry-processing operation. Quality and diligence trump method every time.

Claim 2: "Avoid decaffeinated coffee."

• The Theory: Caffeine has natural anti-fungal properties, so removing it makes the bean more susceptible to mould.

• The Reality: This statement is inconclusive. The beans used for decaf are regular green coffee beans first. Any mycotoxins would likely already be present before decaffeination. Furthermore, modern, high-quality decaffeination methods like Swiss Water® and Mountain Water® involve extensive washing and soaking, which could potentially reduce surface contaminants. There is no clear evidence that the decaffeination process itself increases mycotoxin levels.

Claim 3: "Only buy high-altitude, single-origin beans."

• The Theory: Mould grows less readily at higher elevations, and knowing the single origin of your bean guarantees quality.

• The Reality: This is a massive oversimplification. High-altitude Arabica is grown all over the world, not just in Central America. More importantly, every coffee-growing origin on Earth is capable of producing both spectacular coffee and very poor-quality coffee. Origin is not a guarantee of quality; the farmer's practices are.

Claim 4: "Stay away from blends."

• The Theory: Roasters use blends to hide low-quality beans, so you can't know what you're getting.

• The Reality: This is based on a flawed, cynical assumption. For a professional roaster, blending is a tool for achieving consistency and complexity. Coffee is an agricultural product that changes with every harvest. Blending allows us to smooth out seasonal variations and create a balanced, dynamic flavour profile that single origins sometimes lack. We use our best single-origin coffees to create our blends—the idea that blends are for "hiding" bad coffee is simply false for any reputable roaster.

Where is the Real Risk in the Coffee Supply Chain?

If the processing method and origin aren't the magic bullets, where should we focus? The greatest risks lie in storage and transportation—areas the consumer never sees.

• Storage at Origin: Coffee is grown in developing nations, often in remote, high-altitude areas with limited infrastructure. Beans can sit for months in basic tin sheds in hot, humid conditions while awaiting transport.

• Transportation: The vast majority of the world's coffee is shipped in standard, unventilated shipping containers. Imagine the temperature inside a metal box sitting in the tropical sun for weeks at a port.

• Port Congestion: Delays at ports in countries like Ethiopia, PNG, or Tanzania can leave coffee waiting in suboptimal conditions for extended periods.

These are the stages where mycotoxin development is most likely, yet they are rarely tested or measured until much later in the supply chain.

The Bottom Line for Australian Coffee Drinkers in 2025

So, what's the practical solution? How do you ensure your coffee is safe and of high quality?

1. Stop Looking for a Magic Bullet: There is no single method, origin, or certification that guarantees a "mycotoxin-free" coffee. The entire system, from farm to roaster, currently lacks the tools to reliably track OTA levels on a batch-by-batch basis. Anyone claiming otherwise is likely using it as a marketing tactic.

2. Focus on Overall Quality and Freshness: The best defence against any potential issue in an agricultural product is to choose a high-quality version. Roasters who are meticulous about sourcing high-grade specialty coffee, who have strong relationships with their brokers, and who don't let green beans sit in their warehouse for years are your best bet.

3. Trust Reputable Roasters: In a competitive market like Australia, roasters live and die by their reputation for quality. Increased demand for specialty coffee naturally pushes the entire industry toward better sourcing, storage, and handling practices.

The conversation around mycotoxins is important, but it needs to be grounded in the practical realities of the industry. Instead of falling for the next marketing fad, put your trust in the roasters who are dedicated to sourcing and roasting the highest quality coffee possible.

That commitment to quality is the best assurance you can get.