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Pickup available at Perky Blenders Roasters
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PLEASE NOTE: THIS IS A PRE-ORDER
Your tasting kit will be sent to you in plenty of time for the live global tasting with James Hoffmann 3pm GMT Saturday 3rd October 2026.
Keep an eye on your emails and our socials for more information about the live tasting and everything you'll need to take part. More details coming soon!
ONE COFFEE. FOUR PROCESSES. ONE BIG COFFEE EXPERIMENT.
Coffee geeks, curious sippers and flavour hunters, this one's for you.
We're VERY excited that Perky Blenders is taking part in The Fermentation Project, a global coffee tasting experiment led by James Hoffmann, coffee fermentation expert Lucia Solis, and sourcing partner Caravela.
The idea is brilliantly simple: take one exceptional coffee and process it in four different ways, changing the fermentation while keeping the coffee itself the same.
Same farm.
Same producer.
Same harvest.
Same varietal.
Same terroir.
Four different fermentation methods.
Which means you get the rare chance to actually taste what fermentation does to your coffee.
WHAT'S IN THE BOX?
Your Perky Blenders Fermentation Project Tasting Set contains four 60g bags of whole bean coffee from Finca San Miguel Urias, Guatemala, produced by Hector and Lilian Leal.
That's 240g of coffee in total, with each 60g bag representing a different fermentation method.
Each coffee started life as the same lot, but was processed differently:
01 - Mechanically Demucilaged
The control coffee. No fermentation, giving you a starting point for understanding the flavours coming from the coffee itself.
02 - Wild Fermentation
Fermented for 48 hours using the naturally occurring local microbes, a traditional approach used across much of the coffee-producing world.
03 - Lactobacillus Fermentation
Fermented for 48 hours with an inoculated Lactobacillus culture, exploring how bacteria-led fermentation can influence acidity and complexity.
04 - Yeast Fermentation
Fermented for 48 hours with Saccharomyces yeast, demonstrating how yeast can influence flavour precursors, complexity and body.
Taste them individually, then get them lined up side-by-side and see what you discover.
IMPORTANT: YOU'LL NEED A GRINDER
All four 60g bags in this tasting set are supplied as whole beans.
To get the full experience and taste the coffees at their best, you'll need a coffee grinder at home. We won't be offering a pre-ground option for this project.
Need to brush up on your cupping skills? We'll include a card in your box with a link to a how-to-cup guide, so you can get yourself prepped and ready for the tasting.
WHY IS THIS SO INTERESTING?
We talk about fermentation in coffee A LOT.
Washed. Natural. Anaerobic. Inoculated. Experimental. Wild.
But there's usually one pretty major problem when you're trying to understand what those processes actually do: the coffees you're comparing are different.
Different farms, different varieties, different growing conditions, different harvests.
The Fermentation Project removes those variables.
For once, you can taste the same coffee four ways and explore what changes when the fermentation changes.
It's coffee science but the fun, drinkable kind.
CUP ALONG WITH THE WORLD
And this isn't just happening at Perky Blenders.
Roasters and coffee drinkers around the world are taking part, with thousands of people tasting the same coffees and exploring the results together.
The project culminates in a global virtual tasting hosted by James Hoffmann, so you can brew or cup your Perky set at home and join coffee lovers around the world for one enormous coffee tasting.
Whether you can tell your Lactobacillus from your Saccharomyces or you've never even thought about how coffee is fermented before, you're invited.
No coffee degree required. Curiosity definitely encouraged.
COFFEE DETAILS
Origin: Guatemala
Farm: Finca San Miguel Urias
Producers: Hector & Lilian Leal
Coffee: One lot, four processing methods
Processes: Mechanically Demucilaged / Wild Fermentation / Lactobacillus / Yeast
Recommended brewing: Filter / Cupping
Grind: Whole bean only - you will need a grinder or come to store and we will help you.
Format: 4 x 60g bags (240g total)
Also included: Card with a link to a how-to-cup guide
Availability: Very limited
FOUR 60G BAGS. FOUR PROCESSES. ONE GLOBAL COFFEE EXPERIMENT.
Grab a box, get your grinder ready, get the kettle on and taste along with us and James on the 3pm GMT 3rd of October 2026.