The job of a specialty coffee roaster is to unlock the distinct flavours inside green coffee beans. However, before they do this, they must determine how their coffee is likely to be brewed and roast their coffee accordingly.
This is because coffee intended for espresso-based drinks needs to be roasted differently to coffee intended for filter brewing, such as using a V60 or a Chemex. Factors such as acidity, solubility, body, and flavour intensity mean that roasters need to think carefully about what their customers want before they start roasting.
To find out more about the differences between roasting for espresso and filter, I spoke with Christian Gullbrandsson from Morgon Coffee Roasters in Sweden.
What Are Filter And Espresso Roasts?
In order to develop the flavour locked within green coffee beans, specialty roasters must first make a decision on how they will roast their coffee.
One of the most popular roasts is espresso. Espresso is a method of brewing coffee that originated in Italy at the end of the 19th century. It involves passing a small volume of hot water under high pressure (8-10 bars) through finely-ground coffee beans.
This pressurised brewing method typically results in a thick, highly concentrated, and densely-flavoured cup of coffee that can be enjoyed by itself, with added water, or as a base with milk, such as for lattes and cappuccinos.
An espresso roast, therefore, is one in which the roasted coffee is intended for use in espresso-based drinks. This usually involves roasting the beans well beyond first crack to allow more time for flavour development, to reduce acidity, and to produce more body. The beans will typically appear dark and oily, while a creamy, airy layer will appear on the surface of the coffee when brewed.
The other most popular roast is filter. Filter coffee involves pouring hot water over coffee grounds and allowing gravity (rather than pressure) to pull the extracted coffee down into a cup over a few minutes.
Filter roasts are created for a range of brewing devices, including Chemex, V60, French press, and clever-dripper. They often require the addition of papers – known as filter papers – that enable the water to pass through the coffee grounds without dispensing them into the cup. The result is usually a smooth, light, and clear-tasting coffee.
To achieve a filter roast, specialty roasters typically roast their green beans at lower temperatures and at a shorter period of time than espresso. They will end the roast shortly after first crack to produce a lighter coloured roast profile.
Why Does Coffee Need To Be Roasted Differently?
The reason specialty coffee roasters use different roasts for espresso and filter largely comes down to maximising flavour from each brew method.
Christian Gullbrandsson works at Morgon Coffee Roasters in Sweden. He explains that the purpose of roasting for longer in an espresso roast is based on development. Development generally refers to the last few minutes of a roast, in which the roast profile and flavour are significantly influenced. Depending on the variety of coffee, the less time spent within the development phase, the lighter, more acidic the coffee will taste.
“In an espresso roast, we extend the development a bit to round off the acidity,” he says. “The aim is to create a smoother, more balanced flavour with heavier body. Whereas with filter, we try to produce coffee with higher acidity.”
In addition to higher acidity, one of the reasons for the shorter development time of a filter roast is to produce a more delicate coffee in which the subtle flavours are apparent when brewed. In general, lighter roasts enable consumers to pick up on the distinct characteristics of the beans, such as where it was grown and how it was processed.
With espresso roasts, although the flavours are more intense, the longer development time causes the flavours to become slightly more hidden than in a filter roast. In other words, the roaster imparts greater influence on an espresso than a filter in which factors such as the terroir and processing method have more of an impact.
Another reason specialty coffee roasters use different roasts for filter and espresso is due to solubility. Coffees that have been roasted for espresso generally possess a higher percentage of maillard reaction compounds and have undergone greater bean fibre manipulation. This means that the soluble matter that exists in a coffee roasted for espresso is less volatile than that of a filter roast, making it less readily extracted.
“Given the stability of the soluble compounds in an espresso roast, it’s likely that the delicate brewing conditions of a filter brew will not be sufficient in accessing all the soluble matter,” writes Michael Sleland in an article for Assembly Coffee. “However, the intense pressure of an espresso brew will access all the soluble matter more easily, resulting in a more accurate representation of roast development.”
Do Filter & Espresso Roasts Require Different Packaging?
For specialty coffee roasters, it’s important to make sure customers know precisely what it is they’re buying and how to achieve the best results when brewing.
As well as labelling it as “espresso roast” or “filter roast”, roasters can also include specific brewing instructions. These let customers know which brewing methods are best suited to the coffee in order to make the most of its unique flavours.
Christian says that it’s also important to display the coffee producers and the origin of the coffee to present consumers with a wider picture of the product.
“We like to include details on the coffee’s story, as well as clear flavour notes using stickers on our bags,” Christian says. “This helps customers quickly differentiate between an espresso and filter roast.”
It’s also important for roasters to consider how quickly their coffee will degas after roasting. Degassing is the process by which coffee releases built-up carbon dioxide (CO2) that’s absorbed during the roasting.
Because espresso roasts tend to have longer development times, they have had more time to build up CO2, which is released at a quicker rate once the roast ends compared to filter roasts.
For that reason, roasters should include degassing valves to espresso roast packaging to allow CO2 to escape and avoid rupturing the bag. This could also happen with filter roasts, however but it’s less of an issue when roasters know their coffee will be consumed shortly after it’s packaged than it is for espresso roasts.
At MTPak Coffee, we offer a range of sustainable coffee packaging that will help protect and showcase your coffee at its best. Whether offering coffee for espresso or filter, we can help you choose the perfect coffee pouches and components, from degassing valves to resealable zippers.
With our fully customisable packaging, you can include information on the roast method, roast date, origin, and flavour notes, as well as brewing instructions to help your customers make the most of their coffee.
For information on our sustainable coffee packaging, contact our team.
Stay updated about our products and services. Sign up to our free newsletter.