INTRODUCTION
Coffee brewing is a type of art. Nothing compares to brewing the ideal cup of coffee to your specifications using the proper roast and brewing technique. Selecting the proper roast is one of the most crucial choices you'll make when making the ideal cup of coffee. The flavour, body, and caffeine amount of your brewed beverage will vary depending on the roast level of your coffee beans.
Below are the different stages of roasting green coffee goes through before they are ready to be dropped. Through the application of heat, coffee goes through a series of chemical changes which deliver unique aromatic compounds distinct to coffee which people love so much. The top row shows 4 stages a roast is usually dropped at. Light, Medium, dark and extra dark. At cannon we prefer to have dark as out maximum, given extra dark often delivers carbonised and highly bitter characteristics which tend to be unpleasant.
Let's explore what different roast profiles typically offer, and what works best for you!
LIGHT ROAST
With the shortest roasting period, light roast coffee beans produce a beverage with a bright, sweet and acidic flavours. African coffees tend to be roasted to this profile to preserve unique fruity characteristics. With regards to brewing we highly recommend pour over or Aeropress to best extract these flavours with ease. The 3rd wave of specialty coffee, with focus to artisinal roasting and brewing tends to favour light roast coffees, and have seen a resurgence in the last 10 years.
MEDIUM ROAST
Medium roast coffee beans are roasted for a slightly longer period of time than light roast beans, and is the safest roast profile for basically any origin. Some beans work better as light or dark, but if in doubt a medium roast will hold a good middle ground of giving at least a good amount of unique flavours from that coffee and origin. Medium roast coffee beans produce a cup of coffee that is more intense in flavor and has a slightly more balanced acidity. For brewing, medium roast coffees are best served in cafetière, but also espresso brewing and pour over works well too. Again, the safe versatile middle ground.
DARK ROAST
Coffee beans that are dark roast are normally roasted for the longest, and deliver the most intense and punchy flavours associated with a 'strong' coffee. Coffee beans that have been darkly roasted have a bolder flavour, with a full body, less acidity and more bitterness. A hallmark of a good dark roast is dark in colour but NOT shiny or rancid smelling. Unfortunately some coffee chains dark roast beans for too long, and a shiny surface is a present which indicates rancidity and the coffee going stale very quickly, with much higher bitterness.
Dark roasted coffee has a slightly higher level of caffeine by weight, given less CO2 and moisture is present in the seeds compared to lighter roasts, and by ratio, caffeine content increases.
Typically dark roasts have are tied to origins like Brazil and Colombia known for their bold and chocolate flavour notes. We recommend brewing dark roasted coffee for espresso, give the easy level of calibration for extraction, and delivering the intense strong flavours typically associated with a great shot of espresso.
CLOSING THOUGHTS...
These brewing methods are a rule of thumb, but we highly recommend experimenting different roast profiles for any brew type. Whilst a light roast coffee is typically difficult to dial in for a double espresso, the results can be astounding if you take time to dial in factors like grind size, weight and brew time. Please see our Perfect Espresso Guide for more details.