Shaken or Stirred

Shaken or Stirred

Densification results in more spherical coffee particles, which allows them to pack together more evenly. This in turn would allow water to flow more evenly through the puck. To understand why spherical particles…

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RDT vs The AutoComb

RDT vs The AutoComb

You’ve probably heard that scientists recently caught up with something home baristas have known for nearly two decades: that spraying your coffee with water just before grinding can reduce the amount of static created.

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Grinding Bean-by-Bean

Grinding Bean-by-Bean

Grinding coffee bean-by-bean is up there with cryogenic grinding, double grinding and re-processing as a kind of impractical perfection — all of which are generally dismissed as inappropriate for the commercial environment…

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Round Two — Battle of the Baskets

Round Two — Battle of the Baskets

The defining feature of this new wave of high extraction filter baskets for espresso is the pattern of holes at the bottom of the basket. Manufacturers have completely re-thought the way these are laid out, to ensure even extraction…

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Battle of the Baskets

Battle of the Baskets

The big leap in espresso technology is something brilliantly simple, intuitive and affordable. It’s the ‘high extraction’ filter baskets. Armed with these new baskets and better distribution tools, baristas are making different…

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Tiny Coffee, Massive Bills

Tiny Coffee, Massive Bills

In the face of unchecked price-gouging by energy companies, what can cafe owners do to keep their bills under control? Big savings can be had by ditching boilers for good – and even doing away with the espresso machine altogether…

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The End of First Crack?

The End of First Crack?

Is it possible that neither first crack, nor the precise adjustments to the gas settings that roasters make afterwards, are actually very important in coffee roasting? No matter how complex a roast profile you design for a drum roaster, you could…

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What We Taste When We Taste Acidity

What We Taste When We Taste Acidity

New research published this week, however, suggests that the levels of many of the organic acids found in brewed coffee are so low as to be essentially undetectable (Birke Rune et al 2023).

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Iced Latte Art

Iced Latte Art

Cold foam has become pretty popular over the last few years, and yet, visually, cold foam lattes are firmly stuck in the 1980s. In other words: a tall, layered drink in a glass, topped with a spoonful of stiff foam like whipped cream. Wouldn’t it be great if…

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Wet Weiss for Espresso

Wet Weiss for Espresso

As with all our best and wildest experiments, our investigation of Wet Weiss for espresso began with a conversation with multidisciplinary industrial scientist Professor Abbott. He suggested that adding some water before tamping might allow us to pack the bed of coffee more tightly together.

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Pass the Espresso on the Left Hand Side

Pass the Espresso on the Left Hand Side

If espresso drops unevenly from the spouts of your portafilter, don’t assume it’s down to bad tamping or bad puck prep. More importantly — don’t assume that just because the coffee drops evenly from the spouts, that means that your tamping was perfect!

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The Evaporation Front

The Evaporation Front

In the last few lessons of our Roasting Science course, we’ve been exploring the evaporation front that forms inside coffee beans as they roast. In coffee roasting this phenomenon has an almost mythical status. It has even been touted as a possible cause of first crack, but there’s very little direct study on this topic, and a whole lot of conjecture. In this post…

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Who Really Invented the Air Roaster?

Who Really Invented the Air Roaster?

The invention of the air roaster revolutionised coffee roasting, allowing faster roasts on larger scales than had ever been possible before. In the decades since it was invented, the air roaster became hugely important in industrial coffee roasting — although the classic drum roaster remains the machine of choice for most smaller-scale roasteries …

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The Possibly Lactic Process

The Possibly Lactic Process

The two main players in wild coffee fermentations are yeasts and lactic acid bacteria (LAB). LAB are a broad group of bacteria species that ferment glucose into lactic acid and, in some cases, ethanol. Along the way, LAB produce a lot of delicious flavour compounds — esters, ketones, and aldehydes — that can lend coffee distinctive floral, fruity, creamy, and buttery notes…

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Wet Weiss Distribution

Wet Weiss Distribution

If you have ever ground your own coffee, then you’ve probably tried the Weiss Distribution Technique (WDT). Possibly even without realising you were doing something that had a name, you might have grabbed a paper clip and done a little puck raking just for the pure catharsis of breaking up those clumps of coffee grounds. But have you ever tried doing WDT in wet coffee?

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Post-Roast Sorting

Post-Roast Sorting

If you ever hang out backstage at the World Brewers Cup Competition, you’re very likely to see baristas hunched over trays of coffee, obsessively picking over their beans. Any slight blemish or discoloration, any deviation in size or shape, and the offending bean is plucked out and discarded, until only the most perfect physical specimens are left to face the judges.

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Deconstructed Fermentation

Deconstructed Fermentation

Diego Bermudez uses a multi-stage process to isolate and control the different phases of coffee fermentation — even to the extent of carrying out part of the fermentation away from the coffee beans themselves. The resulting coffees have incredibly intense, fruity flavours that push the boundaries of what coffee can taste like. After several years of experimentation…

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If and When to Stir a French Press

If and When to Stir a French Press

The French press is one of the simplest coffee brew methods in a barista’s repertoire — grind the coffee; add hot water; wait for a bit; give it a stir; plunge and you’re done. Even the plunge is optional. But despite the apparent simplicity, this brewing method has a few snags that we have been trying to work out. For example, we discovered that

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The Mexican Geisha Intrigue

The Mexican Geisha Intrigue

The Geisha variety is one of the big success stories in coffee over the past decade. Ever since the variety’s quality potential was discovered by the Peterson family on Finca Esmerelda, prices of Geisha coffees have broken record after record at auctions. Last year’s Best of Panama winner, from Finca Nuguo, almost doubled the previous auction record with a price of…

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Starter Culture Culture

Starter Culture Culture

Every once in a while, a single cup of coffee comes along that redefines your idea of what coffee can taste like. When that happens to us at BH, it sends us down a rabbit hole: We have to find out what made the coffee taste that way, and what we can learn from the way that particular coffee was made. Our Dean of Studies, Jem Challender, tasted one such cup recently…

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The Group Head Express

The Group Head Express

You’ve dialled in perfectly. You are weighing every single dose, distributing carefully, tamping perfectly flat with a calibrated amount of force — and yet, your shot times aren’t the same. After a few shots you notice it’s always the same group that runs just a few seconds faster — or slower — than the others. Perhaps you start to avoid using that group…

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