Photo credit: Melanie Böhme
Blends are a mainstay of the coffee industry, and a good blend is more than the sum of its parts.
Specialty coffee fans say nothing beats a single origin. Yet blends have their own advantages and appeal. Creating a good blend challenges roasters to demonstrate their highest skills. Whether it’s blending a distinctive product for a trade customer’s premium line or developing a house blend that ensures year-round consistency and broad appeal, the art of the blend requires mastering complexity.
Two leading coffee pros shared their perspectives on crafting quality blends at the Specialty Coffee Expo in Portland, Oregon in April: Mike Ebert, founder of Illinois-based Firedancer Coffee Consultants, and John Gozbekian, owner of Johnny CoffeeSeed, an Arizona-based roastery.
A blend should be approached the same way as a single origin, as Gozbekian sees it. It’s about understanding ingredients and flavor profiles. Think like a chef in a kitchen. Do the flavors match or clash?
Gozbekian recommends that you start with the end product in mind, then look for a specific flavor profile. Will the blend be used for espresso shots? Batch brews? Milk-based beverages?
Think of your customer’s perspective, especially when it comes to espresso blends, Gozbekian said. The key point is this: some 90–95% of espresso blends are mixed with milk, so there is no need to agonize over creating “the perfect espresso,” as roasters often do.
“You’d want a perfect extraction within 20 to 30 seconds with your blend,” Gozbekian said. A good blend will taste great in these 20 to 30 seconds, and the average customer might not have the barista skills to continue to dial in. So, with a blend, you aim for a broad “sweet spot.” A blend for everyday breakfast coffee shops, for example, should withstand a bit of excess weight or an “off grind,” i.e., inconsistency in grind size. A blend is meant to be forgiving.
Synergy
Gozbekian advises cupping when creating a blend just as you would cup for a single origin. You want to know and understand each component coffee first, and then start to create the combination wanted by the customer.
Choose the blend components at the cupping table. Taste them individually side by side. Take notes. Think about which coffees would work together, and in what percentage. Then make the blend and brew it the same way that it will be sold. Don’t overthink it. Just taste it, Gozbekian said.
Create a blend profile that is different than the individual components and better as a whole. It should offer something that doesn’t exist in the individual coffees.
Another approach is to shape the blend to highlight the desirable notes of one of the key component coffees. This especially makes sense when you include a special bean like an Ethiopian Muji for which you paid a premium price, he said.
On the other hand, you should avoid blending coffees that score very high, he says. Coffees that score in the higher 80s, e.g., 86–87, don’t necessarily work well in blends. These beans are better used as single-origin roasts. Food service customers, breakfast cafes, fine dining venues, etc., look for a lower tone. That means coffees scoring between 80 and 85, Gozbekian said.
Chemistry and consistency
Beyond the selection of beans, a successful blend requires understanding the physical and chemical changes that happen during roasting. Beans of various origins have different characteristics that need to be considered.
Some customers want a blend that has year-round consistency. To ensure this result you need to monitor different harvest seasons and how they affect each coffee. For a blend that’s supposed to be the same each and every year, price and quality are indicators that help in selecting specific crops, said Gozbekian.
It takes practice to achieve a well-balanced blend. The roaster must tackle the different characteristics of different coffees through trial and error. Critical factors are the density of the bean, the elevation at which it was grown, and how the coffee cherry was processed.
Elevation matters because for every 300 meters (1,000 feet) higher, a green coffee gains 10% in sugar content. That is because higher elevations are cooler at night, and so the coffee cherries don’t consume as much of the sugars that produce excellent flavors. A coffee grown at a higher altitude is denser. In a 50:50 blend, the difference between coffees grown at lower and higher altitudes might not be noticeable, yet 5–10% of any of those beans will stratify enough that you will have inconsistency in your cup, said Gozbekian.
Many of the macro lot coffees from Brazil or Colombia combine beans from different altitudes. If you use two different elevations from one country in a blend, you should be aware of the features of the beans. Beans grown at lower elevations will have a sweet softness. Those from higher zones will have a bright acidity and crispness. Gozbekian advised roasters to not roast too lightly when combining such beans because of the different densities. Aim to roast to an extent that evens out the differences and makes the blend more homogenous.
What about species? It’s already a challenge to blend two or more arabica coffees. When you use robusta in a blend, it needs to be handled differently, Gozbekian observed. Robusta beans require the use of about 20% more energy during the roasting process because they are grown at lower altitudes and are not as dense as arabica.
Moisture and storage
Blends can help a small roasting plant that needs to use up a past crop because they bought too much of it. But an old crop does not roast the same as a fresh one, and this affects the blend. As a green coffee gets older, it loses moisture. It might taste great, but it does require an adjustment in roasting to achieve the desired results.
Lower grown coffees, such as Sumatran beans that work quite well in blends, tend to have higher moisture content, Gozbekian explained. “So oftentimes in a roaster, you’re hitting them with the same amount of heat in the beginning, but if you keep it going that way that Sumatra is going to take off. So usually, you’ll back it off in this case.”
How well do you store your coffee? Green coffee ages and loses moisture. Gozbekian said that beans that are six months old have changed, but they can still taste great. And in a blend the customer probably won’t taste the difference. A roaster should not be reluctant to ship a blend that uses older green beans.
Pre-blend or post?
You can blend the beans before or after roasting. Deciding on which depends on the goal of the blend, said Ebert, the Firedancer Coffee Consultants founder.
One criterion to consider might be the size of the roasting plant. Blending before the roast works best for a big roasting plant, such as when roasting coffees for breakfast food service. In this case, blending after the roast would require using more warehouse space. “You’d probably need to invest in extra machinery for doing the post-roast blending. With a pre-roast blend you just put the green coffees together. Take each component and blend it in, roast them together, and package it in the packaging machine,” Ebert said.
When pre-blending, different coffees will advance through the roasting process differently. That means it’s important to understand the coffees and how they develop. You must understand roast degrees. If you aim for less acidity, then you will get less fruity and floral flavors and more origin flavors. If you go longer in the roasting process, the next stage will yield less aroma and origin flavors but would provide more body.
Darker roasts, at 40 on the color scale, will give a broader “sweet spot” — i.e., desirable range — and will work well for a blend for everyday coffee shop. A dark roast will marry up with a broader range of desserts and foods. Lighter roasts, around 60 on the color scale, of higher grown coffees, tend to be better with food served in fine dining, e.g., a fine Italian restaurant. You need to work out the nuances of a blend and match it to the likely brewing method, Ebert said.
The bean’s processing method can affect the question of whether to blend before or after the roast. Different processing methods yield beans that roast differently.
Ebert advised against blending roasted coffee beans in the cooling tray, however. This can “bake” the coffee and give it a flat taste.
Gozbekian recommended using equal proportions when starting to create a blend, whether it will be mixed before or after the roast. Then try a mix of thirds or even quarters, making adjustments along the way. In general, a maximum of five coffees can be blended successfully. A blend of more than five coffees becomes “too complex.” A roaster that is just starting out at blending coffees should try working with three, Gozbekian said.
Ebert observed that even Third Wave roasters rely on blends as “bread and butter” — as basic sustenance for their business. Make a blend that meets your own high standards: “Make it something you’re proud of,” he said.