Potato Defect Information and Credit Policy

Coffees from Rwanda, Burundi, and D.R. Congo sometimes contain a pesky, but harmless defect we refer to as “potato” for its obvious and overwhelming potato smell. In an effort to add transparency to what we do while continuing to promote the phenomenal coffees of this region, we are establishing a policy around identifying and crediting bags of coffee with this defect. Such a policy likely raises some important questions! Here’s an ever-updated FAQ to help you understand and navigate these problems:

Why would you offer a defective coffee?
This is really the most important question, and we want to answer it honestly. Coffees from Rwanda, Burundi, and D.R. Congo are often astonishingly good. Without the presence of defect in a cup, many we source are easily 86-points and above. We heavily vet coffees from these regions to find lots that have very few occurrences of the issue. Second, the coffee industry is a booming and important part of the developing economies of these countries, all of which have experienced decades, if not centuries, of economic and violent strife. The communities we are working with are producing specialty coffee because it is a sustainable pursuit. Third, there is not yet a clear cause identified for the potato defect. We are going to link a number of articles later in this post, but please notice the inconsistency. A lot of work is currently being done to eliminate this issue, but we haven’t yet found a method. Turning our back on these communities and coffees seems pretentious, unsustainable, and anti-specialty, in our opinion. We’ve fallen in love with these coffees just because of their amazing qualities. To add to that, we are now becoming more and more invested in the mutual success of our relationships in Rwanda. Our importing partner for Ejo Heza, Artisan Coffee Imports, is well aware of the potato problem, and has created a practice of monitoring for the issue and helping offset the costs of coffee that must be discarded. This has helped and encouraged us to create this policy this year. Mutually beneficial partnerships mean succeeding and struggling together. We invite you to become an advocate for these fine coffees. We believe awareness and transparency are important to the eventual eradication, or identification, of the causes of potato defect.

How will I know if my coffee contains potato defect?
You’ll know as soon as you grind the coffee. The smell from the defect creates and instant and strong smell of raw potatoes. The nice thing about the defect is that it’s easy to identify once the coffee is ground. The hard part about the defect is that it’s impossible (so far) to identify it in the coffee beans before they are ground. If you smell the defect, we recommend discarding the grounds immediately in a separate room or sealed container. The presence of the smell will make it difficult to identify the flaw in the next set of beans you grind. This is especially relevant in a coffee bar or restaurant scenario.

What should I do if I get a potato defect in my bag of coffee?
12oz Bags (local): Simply return the 12oz. bag to either of our locations (6225 Delmar or 4206 Watson), no matter where you bought it, and we will replace the bag with a new bag of the same coffee or another bag of your choosing.

12oz Bags & 2# Bags (online orders or out of town): Send an email to (orders at blueprintcoffee dot com) that identifies the roast date and batch number (on the bottom of the label). Indicate if you would like a replacement of the same coffee or a different coffee. Also, please indicate the shipping address we should send it to. We will then send that replacement to you along with a return label and envelope with which we ask you return the defective coffee.

2# bags & 5# bags (wholesale partners): We ask that our wholesale partners educate themselves and their staff using this post and the links below. We strongly suggest padding the margin on cups of coffee from these regions by adding an addition 3-7% to the sales price. This will allow you to discard the coffee when it is ground in your store and absorb that cost. Consider offering these coffees in small-batch style brewing (pour-over or espresso), so as to be able to identify the defect without grind through a large amount of coffee. If you are retailing bags of our coffee, a sticker guiding your customers to this blog post will be on the back of the bag. They can use the local or out of town instructions to receive credit if they get a defective bag.

Why should I take the risk on these coffees when you have others to offer?
Again, these coffees are astonishingly good and unique. If you are a fan of lively and sweet coffees from further north in Africa (Kenya, Ethiopia), we believe you’ll find a kinship in these coffees during the off-season for northern Africa. Plus, purchasing these coffees creates an active participation in the betterment of the communities that grow the coffee and cooperatives, exporters, and importers who are funding research into the defect.

What causes the potato defect? Will it hurt me?
So far, we have found that research into what causes the defect is inconclusive. Below, find a number of articles about it. In our experience, and the experience of many of our peers in the coffee industry, the defect has no known detriment on human health.


Daily Coffee News: “Potato Taste Defect: What Roasters Need to Know” by Chris Kornman



SCA Coffee News: “Risk, Responsibility, and Potatoes? A Rwandan Coffee Story”



Intelligentsia Coffee: “What to do about Mr. Potato” by Geoff Watts



Agriculture, Ecosystems & Environtment: “Occurrence of potato taste defect in coffee and its relations with management practices in Rwanda” by Joseph Bigirimana, Christopher G. Adams [et. al]