There's something we need to talk about and
it ain't pretty or glamorous
- it's the 'Potato Taste Defect'


We love coffees from central Africa so much so they are featured in this month's coffee subscription (specifically Rwanda and Burundi). They are fantastic examples of what this region offers - and more than that they host completely unique flavours in the world coffee game.

However, there is this one thing that is out of the control of the producers, exporters and roasters - potato defect. Its presence has been drastically culled in the last two decades, turning around an industry that was at the time looking gloomy.  Even the most carefully cultivated and meticulously processed coffees from this region have the defect.  The good news?  It affects 1 bean in 10'000 - that's nothing right? But we want to educate you. It will cause you no harm, it may just surprise you on the odd occasion.  



Potato taste defect is caused by a chemical called 2-Isopropyl 3-methoxy pyrazine (IPMP) that gives the coffee a raw potato-like smell and flavour. The most common cause of IPMP production is damage to the cherry skin from insects or weather, allowing bacteria to get inside and produce this chemical.

You're grinding your cup of morning coffee and all of a sudden there's a waft of freshly peeled potatoes.  Who's prepping lunch you think?  Nope, it's Mr Potato defect!  The potato defect is created by an airborne bacteria that can enter the coffee cherry whenever there is a puncture/tear in the outer skin.

You might ask why sell this coffee if it has the potential to hold defects? Trust us, it's a truly amazing coffee and the producers will do everything in their powers to hand sort and remove any visibly damaged beans that may be affected. Denying ourselves and you the pleasure of tasting the delightful and uniquely delicious coffees from Rwanda and Burundi would be a far greater crime. It is also a matter of principle for us here at RAVE. Producers in Rwanda and Burundi are some of the most under-privileged in Africa, yet they produce some of the most unique and delicious coffees. They deserve our support for the last decade's hard work in elevating their quality.

Operating a zero-defect policy on a defect that only affects one or two seeds at a time seems unreasonable when each container we buy may have more than 100,000,000 seeds in it! We wouldn't mind rejecting a coffee where the processing or fermentation had negatively affected the whole batch, but where only a few seeds are affected? No, that seems impractical!


There are very low, if any, visual identifiers that correlate to potato taste defective seeds. In fact, most defective seeds look perfectly normal to the human eye and show no visible insect damage or abnormalities.

Therefore, unlike other defects, there is no “preventative maintenance” in processing or sorting methodologies that the producer can do to ensure a highly reduced rate of potato defect.

This defect is solely detectable via smell and taste. We have done extensive research to better understand the defect rate in the coffees we source.



When preparing to brew Rwandan or Burundian coffees:

  • Grind beans in small batches instead of grinding a whole bag at once. For home brewing, grind less than 30 grams at a time.
  • Carefully smell the ground coffee before brewing. If you detect a raw potato-like smell, discard that batch of grounds.
  • If the grounds smell fine, you should be good to brew and enjoy your coffee!


If you purchase whole beans from us and you grind your coffee and you get a waft of potato/steamed veg, just throw this small amount of grind away, smile whimsically and try again. The chances are it was ONE bean, and you got unlucky. 

Customers who purchase ground coffee from us, we will do our best to check your coffee when freshly ground so chances are you won't be affected. But in the extremely rare case that you feel your bag may be impacted we will of course replace it. 

You see it's only once the beans are ground that you'll notice the unique aroma, or you'll taste it in the cup. But just to reiterate it's ONE bean in 10'000 that is affected!


Even with the small chance of potato defect, we hope you'll take the opportunity to experience the incredibly unique and delicious coffees from Rwanda and Burundi for yourself. The complex flavours and aromas from this region are truly one-of-a-kind.

We're confident that if you give these coffees a try, you'll fall in love with them just as much as we have. The producers work extremely hard to deliver an exceptional product, and we believe they deserve all our support.

So go ahead - order some bags of our Rwandan and Burundian offerings online today and taste what this region has to offer! You can browse our full range and buy coffee beans online to be shipped directly to your door from our online store.

Let us know what you think of these exceptional coffees from central Africa - we just know you'll be impressed!



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