Omni Roasting


Rebel Deeds leans in to take one last whiff from the trier of Sunergos Coffee’s seventy-kilo Petroncini coffee roaster. Returning the trier to its place, Deeds keeps an eye on the slowly rising thermometer. Beside him, a laptop records the roast profile in real time. As the tumbling drum emits a hearing loss–inducing squeal, Deeds hesitates for a moment before throwing back a lever. Immediately, a rush of coffee tumbles into the spinning arms of the cooling tray.

The above account could describe a daily occurrence in countless coffee roasteries around the world, save for one detail. The 100-plus pounds of coffee swirling in the cooling tray are bound for both the autodripper and the espresso hopper. Sunergos Coffee is part of a growing number of omni-roasters, a group who opts to have one roast profile for all brew methods.

“We don’t have an espresso roast, but we do have an espresso blend,” says Deeds. “We roast every coffee on an individual level. One profile per coffee.”

Conventional wisdom calls for more roast development for espresso than filter coffee. The argument goes that the small amount of water and the short brewing time of espresso demand a more soluble coffee to achieve an ideal extraction. The easiest way to make a coffee more soluble? Roast darker. The omni-roaster movement questions this logic.

Conventional wisdom calls for more roast development for espresso than filter coffee. The omni-roaster movement questions this logic.

“I guess the question would be, ‘Does a coffee that roasts darker or longer really taste better in espresso?’” says Deeds. Rather than developing a separate roast profile for espresso, Deeds seeks to find one ideal profile that works for any brew method. “Roasting is the art of drawing to the surface what’s already in the coffee,” says Deeds. “I’m a treasure hunter that’s out to master that particular bean.”

Chelsey Walker-Watson, cofounder of Seattle’s Slate Coffee, agrees. “We create a unique roast for each coffee that we source to highlight the coffee’s inherent, special attributes and to emphasize a balance of acidity and sweetness,” says Walker-Watson. “At Slate, most of our coffee is roasted the same way regardless of brewing to maintain the sweet and bright taste.” Rather than roasting differently for espresso, Slate relies on the barista manipulating other variables—water, temperature, grind size—to achieve the desired extraction.

The omni-roaster movement is far from monolithic. While Slate’s espresso tends to be light and bright, Sunergos’ espresso falls within more traditional parameters: strong, sweet, with dominate chocolate notes. Broadly construed, omni-roasters can be divided into two clans: those who push their espresso extractions and those who pull back on their filter. In the case of the former, this might entail a higher shot volume, for the latter, a lower water temperature.

Many coffee professionals, however, remain skeptical that each coffee has one ideal roast profile.

(Photo: Nicole O’Banion. Photo at top: Cory Eldridge.)

“Coffee is too complex for us to assume that one roast is going to work with every piece of equipment,” says John Letoto, head roaster at Houston’s Greenway Coffee. “If you’re assuming you can have one roast profile, you’re assuming a lot.” Instead, Letoto sees a spectrum of acceptable roasts.

“Coffee is flexible and dynamic. It can be done two different ways, or multiple ways,” he says. Although Letoto concedes that some coffees work better with omni-roasts than others, he argues the prevailing conventions for roasting espresso exist for a reason.

“An espresso roast is developed for more solubility,” he says, “The more it’s roasted the more brittle the coffee becomes, which allows water to saturate the cell walls.” Letoto insists it’s not just a matter of roasting darker, but how the roaster manipulates the roast profile. “You want solubility of your acids and sugars without solubility of your dry distillates,” he says.

The complexities of espresso extraction, as well as consumer demand, ensure a continuing place for the espresso roast profile.

Proponents of omni-roasting, however, see other advantages to their approach. In addition to streamlining production, Walker-Watson argues it cuts down on waste as well. “As we rest our coffee for a longer period of time after roasting to use it for espresso, we can incorporate any coffee not used for brewed coffee as espresso,” she says. This also allows for new, unconventional tasting experiences.

“We have had great success with roasting according to coffee and not brew method,” she says. “However, many of our coffees present a unique flavor as espresso. For guests seeking traditional, Italian-style espressos, they are often surprised by our offerings.”

So should lovers of sweet, low-acid espresso be threatened by the omni-roaster movement? The complexities of espresso extraction, as well as consumer demand, ensure a continuing place for the espresso roast profile. But for many micro-roasters who lack the volume to develop separate roast profiles for different brew methods, omni-roasting presents what may be the only feasible way to offer a single-origin espresso. Conventions might exist for a reason, but rules are meant to be broken.

Michael Butterworth is the director of education at Louisville’s Quills Coffee and co-founder of the Coffee Compass.