In a market underpinned by single origins and micro heaps, blends have grow to be a standout choice in specialty espresso in recent times. Typically thought of “higher than the sum of their elements”, they provide layered and tailor-made flavour experiences that some single origins can’t present – particularly when ready as espresso.

The most typical method is to mix totally different origins, together with totally different international locations, areas, and farms. Via this system, roasters also can mix coffees which have been processed in several methods or combine a number of varieties collectively to create flavours that attraction to a extra various vary of customers.

Much like processing methodology, roasters must account for every selection’s distinctive affect on a mix. Bean density and dimension, solubility stage, and flavour profile are key components that affect the roasting course of and total outcomes. To realize steadiness and consistency, roasters want to search out the “candy spot” that accommodates all varieties included in a mix.

Carina Esteves and Ishwor Maharjan, the director of operations and head roaster at Baobá Café, Marc-Alexandre Emond-Boisjoly, the founding father of 94 Celcius, and Ashlee Eastwood-Quinn, head of espresso at Rave Espresso, present their perception.

You may additionally like our article on whether or not multi-processed blends dilute or improve flavour.

Understanding the important thing variations between varieties

There are literally thousands of espresso varieties, all of which range in cup high quality and traits. For instance, Bourbon, one of the genetically essential varieties, is famend for its candy and complicated flavour profile, whereas SL28 (a typical selection in Africa) usually has distinctive fruity tasting notes.

Pairing and layering complementary flavours in blends is, in fact, a precedence for any roaster. Whether or not a mix affords familiarity or a differentiated expertise, the flavours of the totally different parts ought to be balanced and synergetic.

However when creating multi-variety blends, roasters want to contemplate different components than flavour profile alone.

“Whereas no two varieties are inherently incompatible, reaching a balanced roast for a mix could be difficult resulting from variations in bean density and dimension,” says Marc-Alexandre, the founding father of 94 Celcius in Montreal, Canada. “Completely different varieties, equivalent to Bourbon, Typica, Caturra, or Pacamara, have distinctive traits associated to dimension, density, sugar content material, and chemical composition.

“For instance, Pacamara, identified for its massive dimension, could be harder to roast evenly alongside smaller varieties,” he provides. “Bourbon and Typica, typically prized for his or her sweetness and readability, could behave otherwise within the roaster in comparison with extra strong, earthy varieties like Catimor or Sarchimor.”

Why is bean density so essential?

Bean density is without doubt one of the key metrics for sorting and grading espresso. It’s primarily the load of a espresso bean proportional to its quantity, which is often influenced by the altitude at which it’s grown. Larger altitudes enable espresso to ripen extra slowly, leading to denser beans with the next sugar content material – making them extra fascinating to many patrons.

Density additionally varies between totally different varieties, too. Bourbon, Gesha, and Wush Wush, as an illustration, are usually dense beans, whereas robusta varieties grown at decrease altitudes are much less dense.

Along with exhibiting extra advanced, candy flavours, denser beans additionally require a special method to roasting.

“Though it relies on roast profile, batch dimension, and origin, the next density selection requires the next begin (or cost) temperature, whereas the other is true for decrease density beans,” say Carina Esteves and Ishwor Maharjan, the director of operations and head roaster at Baobá Café in Lisbon, Portugal. The roaster additionally has areas in Brazil, the place it operates a farm that it sources espresso from.

“Our blends are developed on-farm, and our staff chooses varieties with related sizes and densities to facilitate the roasting course of,” they add. Important variances in dimension and density will depart larger and denser beans underdeveloped, whereas much less dense and smaller varieties will probably be tipped or scorched.

“Dense coffees typically have extra nuanced flavour profiles at a wider vary of roast ranges. Nonetheless, they are often simpler to under-roast as they require extra time and warmth within the machine,” Ashlee Eastwood-Quinn, head of espresso at Rave Espresso. “The dense beans can even be much less brittle when roasted and due to this fact produce fewer fines when grinding. Fewer fines lead to even extraction of and a well-balanced flavour profile.”

Prioritising consistency with multi-variety blends

Combining similar-sized and equally dense varieties looks like a logical method to bypass the challenges of mixing beans of various sizes and densities. Nonetheless, it’s not all the time so simple.

“Reaching the perfect outcomes when roasting blends is usually a means of trial and error. Whereas utilizing varieties with related sizes and densities can, in concept, result in a extra uniform roast, the end result relies on a number of components, together with the particular traits of the varieties and processing methodology,” Marc-Alexandre says. “In apply, mixing varieties with related sizes and densities makes it simpler to attain a uniform roast. Beans of comparable bodily traits take up and retain warmth extra evenly, decreasing the chance of over or under-roasting some parts of the mix. 

“Nonetheless, uniformity in dimension and density doesn’t assure compatibility by way of flavour,” he provides. “That’s why trial and error is so essential; roasters must experiment with how the mix parts behave within the machine and make sure that the ensuing flavours are harmonious.”

Recurrently cupping combos of various varieties utilizing varied ratios is the easiest way to make sure the flavours match and complement each other.

Nonetheless, the method used to mix totally different varieties additionally performs an essential function.

“When mixing a high-density washed Ethiopian selection with a low-density pure Brazilian espresso, roasting them collectively could be problematic,” Marc-Alexandre says. “The Brazilian beans, being much less dense and infrequently bigger, roast sooner, whereas the Ethiopian beans take longer to develop. This disparity can result in an imbalanced cup, with the Ethiopian beans doubtlessly under-roasted and the Brazilian beans over-roasted.”

Publish-roast mixing

“Some coffees would possibly roast to a darker diploma than others when uncovered to the identical roasting situations,” Carina and Ishwor say. “To beat this, roasters can mix post-roast, the place they roast every selection individually to their optimum stage after which combine the batches collectively.”

This enables for exact management over every mix part, making certain that roasters can totally develop their distinctive qualities to create a balanced flavour profile.

Do sure varieties pair nicely in blends? 

Espresso varieties have their very own distinctive traits by way of flavour, physique, mouthfeel, and aftertaste, so understanding which of them complement one another is essential when making a multi-variety mix.

“Some varieties naturally pair nicely collectively in blends, making a harmonious and balanced cup that highlights their particular person strengths,” Marc-Alexandre explains. “For instance, African varieties like 74110, SL28, Ruiru 11, and Konkaka constantly produce distinctive outcomes when blended. Even when sourced from totally different areas or continents, they mix seamlessly to create a cup with layered complexity and readability. SL28’s daring acidity can improve the sweetness and steadiness of Ruiru 11, whereas 74110’s floral and citrusy notes can pair splendidly with Konka’s berry-like sweetness or natural undertones, as an illustration.”

Unique varieties like Gesha and Sudan Rume have taken specialty espresso by storm over the past decade. Revered for his or her distinctive and complicated cup profiles, they’re typically bought and marketed as single origin heaps to showcase their distinctive flavours.

However Marc-Alexandre highlights how these varieties also can work nicely in blends.

“Gesha is usually used so as to add floral notes, delicate acidity, and tea-like qualities to the cup; it pairs splendidly with varieties that supply complementary sweetness and physique,” he says. “For instance, combining Gesha with Bourbon highlights Gesha’s floral magnificence whereas including construction and sweetness from the Bourbon. Equally, pairing Gesha with Caturra or Catuai can steadiness its delicate character with enhanced physique and depth.”

No selection is an island: Espresso flavour is interconnected

The flavour profiles of various varieties are inherently tied to many different components, equivalent to origin, processing methodology, altitude, and terroir. In lots of circumstances, it’s tough to tell apart between the affect of every variable, which implies roasters must account for all of them when creating a multi-variety mix.

“Each ingredient can affect flavour. For instance, SL28 is a typical selection in Kenya. Should you take this espresso and develop it in Colombia, you will get a special flavour profile, even when each coffees are washed,” Ashlee says. “Kenyan washing kinds are additionally very totally different from Colombia, so the flavours we affiliate with SL28 are so closely tied to our associations of Kenyan espresso and processing. Due to this fact, we will make some assumptions when roasting and mixing, however earlier than sensible experimentation takes place, we will’t make sure of something.”

Multi-variety blends can supply roasters some extent of differentiation, creating tailor-made and thrilling flavour combos that go well with a spread of shopper wants. Bean density and dimension are key issues when mixing a number of varieties, however components like origin and processing methodology are additionally play an essential function.

“The last word success of a mix relies on understanding the distinctive properties of every part and tailoring the roasting method accordingly,” Marc-Alexandre concludes. “Roasting espresso is as a lot about science as it’s about artistry and experimentation.”

Loved this? Then learn our article on how blends can cut back waste.

Photograph credit: Rave Espresso

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