Exploring the science behind our new pour over method at DOCR
At Dessert Oasis, transparency is key. We take pride in thoughtfully roasting and brewing all our coffee — always striving to serve the best cup possible on behalf of our producers and our customers.
Recently, we made a shift in our pour over method behind the bar. The change? A longer bloom time, inspired by the book The Physics of Filter Coffee by Jonathan Gagné.
From the Lab to the Bar
If you're a coffee enthusiast or barista interested in the why behind brewing methods, we highly recommend Gagné’s book. In his intro, he shares that every insight came from his very own kitchen-turned-laboratory. As both a physicist and a coffee nerd, he’s uniquely equipped to study the science behind brewing — and the findings are fascinating.
Gagné’s approach helped us rethink our process at DOCR, especially when it came to improving clarity and flavor balance in our pour overs.
Out with the Old
As Education Department managers, Tyler and I have spent a lot of time testing pour over techniques using our go-to brewer, the Hario V60 — a classic cone-shaped dripper with ridges that promote even extraction.
We’ve been consistently testing and performing different brewing methods in search of the ultimate brew for our coffees. During this process, we found it was difficult to achieve the clarity — or separation of flavor — that we sought after. With our previous method, we felt certain flavor notes were getting muddied together, especially in coffees with delicate floral or bright acidic qualities. They just weren’t shining the way we knew they could.
Admittedly, there’s no perfect, one-size-fits-all method. But we were determined to find a recipe that would suit all our coffees better — with more clarity, complexity, and consistency.
Our previous brew recipe looked like this:
Dose: 22g coffee
Bloom: 40–50g water for 25 seconds
Pulses:
150g
200g
250g
300g
350g
Less Pulses, Less Flavor?
We also tested simplified brew methods with fewer pulses — ones popularized by specialists like James Hoffmann and Lance Hedrick. The idea behind fewer pulses is to reduce agitation and achieve a cleaner cup. But in our experience, this often dulled the flavor rather than enhancing it. The coffees ended up tasting flat and lacked the complexity we were hoping for.
This difference became especially noticeable as the brews cooled — which is often when the most dynamic flavors emerge.
Cool Coffee, Clearer Taste
Here’s a fun fact: sweetness and acidity in coffee become easier to detect as it cools. At high temps, our taste buds aren’t well-equipped to perceive these qualities, but as the coffee cools, its complexity is revealed. It’s a bit like how warm milk tastes sweeter than hot milk — the lower the temperature, the more we can pick up on subtle flavor notes.
Unfortunately, in our tests with fewer pulses, we weren’t seeing that usual rise in complexity as the coffee cooled. In fact, the cups seemed to fade in flavor — not build.
Enter: The Longer Bloom
The breakthrough came from a single line in Gagné’s book:
“Using 2 to 3-minute preinfusions has increased average extraction yields by as much as 1%... as well as improving their taste.” — The Physics of Filter Coffee, p. 88
That raised an important question: Have we been behind the bloom game all this time?
What Is Preinfusion?
Before we dive into why this matters, let’s break down what preinfusion — or the “bloom” — actually is.
In pour over brewing, the bloom is the initial pour of water onto your coffee grounds. It’s usually just enough to saturate the grounds — no more, no less. At DOCR, that’s typically 40–50g of water for our standard 22g dose of coffee.
This phase allows carbon dioxide (CO₂) to escape — gas that’s produced during the roasting process, specifically starting during the caramelization of sugars (a phase called the Maillard Reaction). The CO₂ gets trapped in tiny cellular chambers inside the coffee.
Grinding coffee breaks open some of those chambers, but not all. If too much CO₂ remains, that gas can push the water away from the coffee later in the brew, prohibiting extraction. By letting the grounds sit with water during the bloom, you’re allowing CO₂ to escape from the grounds — ensuring an even, more uniform extraction.
If you skip or rush this step, that gas can act as a barrier, pushing water away from the grounds and blocking flavor extraction.
The Longer the Bloom, the Better the Brew
So what is Gagné really saying? That a longer bloom gives more time for CO₂ to escape — which opens up the grounds for better extraction. If you rush it and start pouring more water too soon, the gas gets pushed out while you’re trying to extract, causing uneven results and less flavor clarity.
We took this theory and put it to the test. We tried one of our previously tested recipes — this time with a longer bloom of about 40 seconds.
It was a game-changer.
We began tasting some of the best cups we’ve ever had of our own coffees. Suddenly, the delicate florals, sparkling acidity, and layered sweetness were all shining clearly. The longer bloom gave the coffee more room to breathe — and it showed in every sip.
Our New Pour Over Recipe
After weeks of testing, here’s the recipe we landed on:
Dose: 22g
Bloom: 40–50g water for 40 seconds
Pulses:
200g
275g
350g
This method delivered on all fronts: more complexity, brighter flavor, and better consistency across our cafés. Plus, with fewer pulses, it’s more efficient for our baristas behind the bar. It’s wild that a similar recipe to what we were trying originally, with one small change, can be the key to our perfect cup!
Science Wins
It’s wild how one small adjustment — backed by science — can have such a huge impact on flavor. We’re thrilled with the results and excited to keep sharing what we learn along the way.
If you're brewing our coffees at home with a Hario V60, we highly recommend giving this method a try. And if you’re hungry for more coffee theory, tips, or training, check out our public classes on Eventbrite. We also offer one-on-one training sessions through our Open Lab Hours. We’d love to help you level up your brew game.
Check out our video tutorial on how to brew a pour over with our new recipe below. We're brewing our latest coffee release, Rwanda Ejo Heza!
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About the writer: Emma LaVoie is the Education Manager for Dessert Oasis Coffee Roasters. She's the brains behind this blog and lit a fire under our team to follow suit. You can almost always find Emma reading a book with a coffee in hand. If you're interested in reaching out to Emma, shoot her an email: emma@dessertoasiscoffee.com. She'd be happy to geek out over coffee with you. (Seriously, don't hesitate to reach out — she'll love it.)