For many years, “light roasts” have formed an integral part of the third wave specialty coffee sector.
So called due to their light brown colouring, they are often held in high regard among specialty coffee consumers thanks to their typically bright acidity and complex flavour profiles.
However, while light roasts undoubtedly have their benefits, they may not be the best option for all coffee roasters.
Not only can roasting them be difficult to master, they can also alienate large swathes of consumers who prefer the balanced characteristics typical of medium roasts.
To find out more about light roasts, I spoke with 2019 World Cup Tasters Champion and founder of Sumo Coffee Roasters in Dublin, Daniel Horbat.
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What are the differences between roast profiles?
During a roast, a number of transformations take place. The size, density, and weight of coffee beans change, while characteristics such as mouthfeel, acidity, and body develop.
They also experience what’s known as “first crack”, an exothermic reaction that occurs at around 196°C, and, if roasted longer, “second crack” at around 224°C.
In addition to roasting software, specialty roasters can pay close attention to these physical changes to find the perfect roast profile for their coffee.
However, without a doubt one of the most useful visual cues is colour. As the roast progresses, the beans go from green to yellow to varying degrees of brown.
“Roasting longer and darker will decrease the density of the bean…”
By itself, this colour change is of limited use. But when complemented by other cues such as first and second cracks, and aroma development, colour can be extremely informative.
Early on or just after first crack, the beans tend to be light brown in colour. When they are at this stage, acidity is usually high, body is light, and bitterness is low. In the cup, they often have floral and fruity aromatics, sometimes with hints of caramel.
When the coffee is developed until just before second crack, it turns a darker shade of brown. The acidity becomes more balanced, while body and caramel flavours become more pronounced.
Anything beyond second crack is generally what’s known as a “dark roast”, in which the beans become oily and start developing more burnt flavours that tend to mask the coffee’s unique character.
“Roasting longer and darker will decrease the density of the bean, more gases will develop, and oils start to appear,” says Daniel, who founded his own roastery after winning the World Cup Tasters Championship in Berlin. “All those factors will make the coffee taste smoky and burnt with a long, bitter aftertaste.”
Why do roasters light roast their beans?
Before the emergence of a third wave specialty coffee culture, dark and medium roasts were generally the go-to for coffee businesses, with light roasts considered the preserve of Nordic roasters.
However, as interest in the unique characteristics of coffee have grown, more and more roasters have started adding light roasted coffees to their menus.
Today, a large portion of what’s considered “specialty” coffees are light roasts, with many consumers championing their vibrancy, bright acidity, and subtle complexity of flavours.
Daniel tells me that at his roastery in Dublin, they prefer light roasts because of their ability to highlight various qualities in the beans.
“At Sumo Coffee Roasters, we only sell light roasted coffees for filter and espresso,” he says. “We have a mission in moving coffee forward by putting the farmers on the map and highlighting the terroir, the variety and unique process.
“And to do that we can only roast light in order to preserve those unique characteristics that our coffees possess.”
Light roasts also tend to have a higher caffeine content per brew than when the same beans are dark roasted. The reason for this is that the longer beans are exposed to heat, the less dense they become. As a result, when dark roasted beans are weighed, there are generally fewer than when the heavier, denser light roasted beans are weighed.
Because each bean contributes its own amount of caffeine to a brew, the greater number of light roasted beans required to make a coffee means that the drink will typically be more caffeinated.
This is contrary to the belief of many that darker roasted coffee, with its strong, bold flavours, has a higher caffeine content.
The argument for medium roasts
Although light roasts tend to reveal more complex flavours, the majority of coffee drinkers continue to prefer medium to dark roasts.
Indeed, a recent survey revealed that just over half of US consumers buys medium roast coffee – compared to just 15% for light roasts. This is perhaps what prompted Rao to label medium roasts “crowd pleasers”.
While there may be a number of driving forces behind the popularity of medium and dark roasts, one of the most significant is the preference for espresso-based drinks.
Espresso-based drinks are those such as flat whites, lattes, and cappuccinos, which rely on the inclusion of steamed milk. To complement the sweetness of the milk, the coffee needs to be sweet too. However, this doesn’t tend to be the case with light roasted coffee as it hasn;t had enough time to caramelise during the roast.
Medium roasted coffee, on the other hand, is the perfect accompaniment, thanks to its balance of body, acidity, and sweetness.
This is why brands like Starbucks and Costa roast their beans darker: they know that the majority of their customers will be ordering espresso-based drinks with milk.
If they were to light roast their beans, customers would not only miss the subtle flavours in the coffee, but also be put off by the unsavoury combination of high acidity and milk.
Furthermore, it allows these brands to offer a more consistent, uniform product with which customers can become familiar. With light roasts, there tends to be more variance in flavour and aromas, whereas if roasters develop their coffees for longer, the coffee adopts a more homogenous profile.
This, Daniel points out, can be an effective way for coffee businesses to save money.
“I believe it is not necessarily the roast level, but the lower price cost,” he says. “In order to save money, some roasters will buy low-grade coffee with many defects. But then, by roasting darker, those defects will be more difficult to identify by the consumer.”
Whether roasting light, medium, or dark, choosing packaging that preserves your coffee and showcases the quality of the beans is of the utmost importance.
At MTPak Coffee, we have a range of sustainable coffee packaging options, from kraft paper flat bottom pouches, to LDPE side gusset bags. All our options are either recyclable, compostable, or biodegradable, while our additional components, such as degassing valves and resealable zippers, can also be recycled.
What’s more, our environmentally friendly printing methods and low-VOC water-based inks will ensure you have a fully sustainable product, keeping you ahead of the competition.
