Ochratoxin A in Robusta Coffee: EU Limits and Drying Controls

Quick answer: Ochratoxin A (OTA) is a toxin produced by certain moulds, and in coffee it is linked mainly to slow or interrupted drying, damp storage and rewetting during transport, not to the coffee species itself. Since 1 January 2023 the EU has capped OTA at 3 µg/kg in roasted coffee and 5 µg/kg in instant coffee. Regulatory summaries report no federal numeric limit in the United States, and neither the EU nor Codex sets a limit for green beans, so buyers of Fine Robusta rely on supplier controls, moisture data and lot-level testing.

What ochratoxin A is and where it comes from

Ochratoxin A is a mycotoxin, a toxic compound made by some moulds of the genera Aspergillus and Penicillium. Species named in the literature include Aspergillus ochraceus, A. carbonarius and A. niger. In food, OTA forms mainly when crops are dried or stored in conditions that let these moulds grow. The European Commission's regulation that lowered coffee limits states that OTA forms during sun drying and storage of crops and that good drying and storage practices can prevent it.

For coffee buyers the practical point is that OTA is a process-control problem. It is not something that appears because a lot is Robusta, or because it comes from a particular country. It appears when moisture and time give mould the opportunity, and that opportunity can occur at the farm, at the drying yard, in a warehouse or inside a shipping container.

Regulators take it seriously because of its toxicity. EFSA published a risk assessment of ochratoxin A in food in 2020 (EFSA Journal 18(5):6113), which underpins the current European approach. This article does not summarise the toxicology; it focuses on what a coffee buyer can control.

Where in the supply chain the risk arises

The European Coffee Federation's 2022 guidelines for preventing OTA in coffee identify the main control points: good harvesting, elimination of risky defects, rapid drying to a moisture content between 8% and 12.5%, and clean, dry storage and transport that avoids rewetting the coffee. The 8% to 12.5% range reflects International Coffee Organization Resolution 420, and the guidelines note that some EU member states specify slightly different figures in national law.

The guidelines also make two points that help with interpretation. First, the green bean is protected from contamination by the skin of the cherry, which is why harvest quality and the condition of the cherry matter. Second, EFSA has identified that controlled humidity and temperature during storage can prevent fungal growth.

Applying that to Robusta, an interpretation of ours rather than a finding from a specific study: Robusta is frequently dried as whole cherry, so it spends longer at moisture levels where mould can grow, and drying discipline (layer depth, turning frequency, protection from rain, and avoiding contact with soil) is what separates safe lots from risky ones. The species is not the variable; the drying process is.

Legal limits: EU, United States and national rules

European Union. Commission Regulation (EU) 2022/1370 of 5 August 2022 amended Regulation (EC) No 1881/2006 and lowered the maximum levels for OTA in certain foods, including roasted coffee and soluble coffee. The new levels apply from 1 January 2023. Secondary summaries put the limits at 3 µg/kg for roasted coffee and 5 µg/kg for instant coffee. Products lawfully placed on the market before that date could remain on sale until their date of minimum durability.

Green coffee. A review of OTA in coffee reports that the FDA, Codex Alimentarius and the EU have not established OTA limits for green coffee beans, while some countries have set national limits, with Italy, Finland and Greece cited at 8, 10 and 20 µg/kg respectively. Because the EU limit applies to roasted and instant coffee, importers of green beans into the EU still work backwards from the roasted limit.

United States. A January 2026 regulatory-intelligence summary states that no federal maximum limits exist for OTA in coffee or cocoa. We have not verified this against FDA documents, so US importers should confirm with a customs broker or food-safety adviser.

Why EU limits matter beyond the EU. The same summary notes that EU maximum levels function as de facto trade standards, and that products not bound for the EU are frequently tested against them upstream. EU import checks regularly test for OTA; the AGRINFO programme reported 33 exceedances of OTA maximum levels across food categories in the first eight months of 2022.

What surveys show about actual levels

Detectable OTA is common in retail coffee, but typical levels sit below the limits. A Polish-led study by Zapasnik and colleagues, published in Molecules in 2022, tested products bought in local markets. It found OTA in 17 of 19 roasted coffee samples, with a mean of 0.79 µg/kg among positive samples and a range of 0.44 to 2.29 µg/kg. Instant coffee samples had a higher mean of 3.00 µg/kg, with a maximum of 5.15 µg/kg. That top value is slightly above today's 5 µg/kg EU limit for instant coffee, although the study was published before the 2023 limits took effect. The authors also detected 2'R-ochratoxin A, an isomer, in some samples, and concluded that daily intake from coffee and cocoa would stay below the tolerable daily intake even at the highest levels they found.

These figures illustrate two things. First, OTA is a low-level, widespread contaminant, so buyers should think in terms of margins below the limit, not zero. Second, format matters: instant coffee tested higher than roasted coffee in this survey, which is why the EU treats the two categories differently.

Upstream controls that reduce the risk

The European Coffee Federation guidelines are directed at roasters who buy from origin. The questions below are our translation of those control points into buyer language, not quotations from the guideline.

• Harvest. Are ripe cherries selected, and are overripe, fallen or ground-contact cherries kept out of the main lot?
• Defect removal. Are risky defects, which the guidelines say should be eliminated, sorted before export, and how does the supplier define which defects count as risky?
• Drying. How quickly is the coffee brought to the 8% to 12.5% moisture range? Is drying on raised beds or clean surfaces, with protection from rain and dew?
• Storage. Is coffee stored in dry, ventilated warehouses, off the floor, away from damp walls?
• Transport. Are containers checked for leaks and condensation risk, and is the coffee protected from rewetting between mill and port?

The guidelines also say some suppliers may need to be instructed in good agricultural practice, particularly in how they dry, and that this is a normal part of a buyer relationship rather than a sign of a bad supplier.

Buyer-side verification

Beyond asking questions, a Fine Robusta buyer can build simple evidence into every purchase.

1. Moisture and water activity at arrival. Moisture in the 8% to 12.5% range is the baseline, and water activity gives a more sensitive view of mould risk. See Water Activity vs Moisture in Cambodia Robusta for how the two measures differ.
2. Lot-level OTA testing. Ask for a certificate from an accredited laboratory for each lot, or commission your own test on the pre-shipment sample. The European Coffee Federation guidelines mention a validated method covering roasted coffee from 0.2 to 5.5 µg/kg, which is a useful reminder that the method's range should bracket the limit you care about.
3. Drying records. Request harvest date, drying start and end dates, and how weather interruptions were handled.
4. Storage and shipping records. Ask when the coffee was milled, where it was stored, and how it was packed for transport.
5. Traceability to lot. A test result is only useful if it can be tied to the exact lot in the container. Keep lot IDs in every document.

For the documents involved in a first purchase, see How to Import Cambodian Coffee.

Putting it into a purchase specification

A buyer who wants these controls to be enforceable can write them into the contract. A typical specification for a Fine Robusta lot might state the accepted moisture range, require an OTA result from an accredited laboratory for the specific lot, name the test method and reporting limit, keep a retained sample from the pre-shipment approval, and say what happens if the arrival sample does not match: rejection, re-test by an independent laboratory, or price adjustment. None of these clauses is specific to Cambodia, and none replaces legal advice, but they turn a general concern about mould into a checkable condition.

Is roasting a fix?

Not reliably. The evidence is mixed. A study in the Journal of Agricultural and Food Chemistry on the influence of roasting levels began from the observation that earlier investigations of roasting and OTA were inconsistent and contradictory. It reported that roasting reduced OTA in green coffee, with high percentages of reduction in the most contaminated samples and reductions above 90% under roasting parameters typical of Italian espresso. That is one study, and it does not remove the need to control the green coffee: the EU limit is applied to the roasted product, and a buyer cannot know in advance how much a given roast will remove. Treat roasting as a possible additional reduction, not as a substitute for drying and storage controls.

What this article cannot tell you

• Cambodia-specific data. We did not find published OTA survey data for Cambodian Robusta, so the general controls above are drawn from European and international guidance.
• Species differences. We found no study that establishes Robusta as inherently more or less OTA-prone than Arabica; the risk depends on processing and storage.
• Legal certainty. Limits and testing rules change. Confirm current requirements for your destination market.

Frequently asked questions

What is the EU limit for ochratoxin A in coffee?

Since 1 January 2023, 3 µg/kg for roasted coffee and 5 µg/kg for instant coffee, under Regulation (EU) 2022/1370.

Is there a US limit for OTA in coffee?

A January 2026 regulatory summary says there is no federal numeric limit. Verify with the FDA or an adviser before relying on that.

Is Robusta more likely to contain ochratoxin A than Arabica?

We found no evidence that species alone determines OTA. Drying, storage and rewetting conditions are the drivers.

What moisture level reduces OTA risk?

The European Coffee Federation guidelines point to rapid drying to between 8% and 12.5% moisture, followed by dry storage and transport.

Can roasting remove ochratoxin A?

One study reported large reductions during roasting, but results across studies are inconsistent. Control the green coffee first.

Limitations

This article relies on a European industry guideline, regulatory summaries, a peer-reviewed survey and secondary trade sources. We read excerpts of the guideline and some other documents rather than full texts, and the US position comes from a regulatory-intelligence summary that we did not cross-check with FDA. It is a research summary and not legal, laboratory or food-safety advice.

Sources

• European Coffee Federation, 'Guidelines for the prevention of OTA occurrence in Coffee' (February 2022): https://www.ecf-coffee.org/wp-content/uploads/2022/02/Guidelines-for-the-prevention-of-OTA-occurence-in-Coffee_February2022_FINAL.pdf
• AGROLAB Group, 'Ochratoxin A: new regulation for maximum levels': https://agrolab.com/en/news/food-news/4133-ochratoxin-a-new-regulation-for-maximum-levels.html
• COLEAD AGRINFO, 'Maximum levels of ochratoxin A': https://agrinfo.eu/book-of-reports/maximum-levels-of-ochratoxin-a/pdf/
• DigiComply, 'Ochratoxin A in Coffee and Cocoa: Regulatory Limits and Compliance Reality' (January 2026): https://www.digicomply.com/blog/ochratoxin-a-in-coffee-and-cocoa-regulatory-limits-and-compliance-reality
• DigiComply, 'EU Updates Maximum Levels for Ochratoxin A in Certain Foodstuffs': https://www.digicomply.com/blog/eu-updates-maximum-levels-for-ochratoxin-a-in-certain-foodstuffs
• Zapasnik et al. (2022), 'Ochratoxin A and 2'R-Ochratoxin A in Selected Foodstuffs and Dietary Risk Assessment', Molecules 27(1):188: https://www.mdpi.com/1420-3049/27/1/188
• 'Influence of Roasting Levels on Ochratoxin A Content in Coffee', Journal of Agricultural and Food Chemistry: https://pubs.acs.org/doi/abs/10.1021/jf030116p
• Review of OTA levels and regulatory limits in coffee (table of EU regulatory limits), ResearchGate: https://www.researchgate.net/figure/2-EU-Regulatory-Limits-ochratoxin-A-Levels-in-Coffee_tbl2_282595242