Light Roast vs Dark Roast February 02 2014, 0 Comments
Lights, camera, action! That's right, we at Flight decided to get our film making on; this is Wellywood after all. With a few questions coming in about why we roast our coffee lighter than what some people are used to, we decided to make a short documentary to answer some of them, as well as give Richard his time in the spotlight. So while the documentary is being cut down from about an hour of giggling and bloopers to roughly one to two minutes of informative gold - plus the addition of lots of special effects - this blog post will act as a bit of useful supplementary reading.
Meg checking on her roast.
Richard and Meg cover the basics of the roasting process in the documentary and explain terms like "first crack" and a "Maillard reaction", contextualising them and providing insight as to why we roast lighter than some of the other coffee roasters around. But first of all I think I'd better introduce our big lady, the lovely UG22 Probat coffee roaster; you may call her Betty. She's a three burner, 22 kilo, drum roaster and also outrageously blue. Green coffee gets loaded in to her hopper at the top and the drum constantly turns for the duration of the roast to ensure the beans are roasted evenly, after which the beans spill out in to her cooling tray, completing the transformation from green to a chocolate brown.
They call her... Betty.
I think the easiest way to think about the whole roasting process is to compare it to baking bread. The browning of bread when it is baked or toasted is what is happening to the coffee beans as they turn from green to brown. The browning process is known as the Maillard reaction, which is a non-enzymatic reaction. I won't go in to what a non-enzymatic reaction is, to avoid getting too technical, but such a reaction is usually caused by heat, as opposed to enzymatic browning, which can be seen in the browning of bananas. This reaction starts to happen at around 150 degrees celsius and the longer the beans are being roasted the browner they get, like toast, except a lot tastier. Eventually when the roast reaches between 190 and 205 degrees celsius, the beans give off an audible crack, sounding a bit like popcorn, and is referred to as the "first crack".
Beans cool off in cooling tray after "first crack".
At the first crack the distinct flavours of the bean start to develop and most specialty coffee roasters generally don't leave the beans in the roaster much longer than the first crack. The longer they are left in the caramelisation of the sugars starts to burn and roast out the individual characteristics of the coffee and introduce roast flavours such as: charcoal, carbon and tobacco. Somewhere after the first crack and before the second is the sweet spot that achieves the right balance between sweetness, acidity, body and bitterness, and all varies from origin to origin.
Fun Fact: the caffeine content in the bean actually decreases the darker it is roasted.
Meg lovingly looking over her coffee.
Instead of roasting darker and having heavy roast characteristics in the coffee, Meg and Richard aim to roast in such a way that the specific flavours of the coffee's origin are highlighted and brought through in the cup. So when you have your daily dose of amazing, you won't even know Meg or Richard were there.