Although the roasting procedures are typically quite similar, a light roast and dark roast coffee can vary greatly in their taste, flavour, and body. These differences are due largely to two variables: the roast duration and the roast temperature, which ultimately results in varying colours, moisture levels, and flavour profiles.
A light roast coffee will have a more pronounced acidity than a dark roast, and will have nicely developed flavours which reflect their region of origin. As a result, lighter roasts of coffee are known to have a more complex flavour profile, often featuring a subtle sweetness, fruity tanginess, and floral aromas, depending on their origin. These coffees tend to be more polarizing to customers due to their bright and intense flavours.
Dark roast coffees, on the other hand, are roasted at higher temperatures for longer periods of time. As a result, these coffees are much lighter in weight and more bold and rich in flavour; typically featuring a nutty or chocolatey flavour with hints of brown spices such as nutmeg. These coffees typically produce a cup of full of flavour, rich texture and body, which traditionally has made them a more popular choice.
It’s common coffee lore that light roasts also contain more caffeine than their darkly roasted counterparts, but this difference is marginal and attributable to their difference in density. For the true coffee enthusiast, we recommend choosing whatever roast you prefer and then weighing your beans instead of measuring them. By doing so you will ensure you get a properly balanced cup full of flavour and caffeine, regardless of the roast you choose.
Despite the similarities in their roasting methods, light roasts and dark roasts actually vary quite greatly in body, flavour, and taste due to slight differences in the temperature and duration of the roast. In a light roast you can expect a well pronounced acidity which comes through in the form of a subtle sweetness, fruity tanginess, or floral aromas. In a dark roast you can expect a richer texture and body with notes of chocolate, nuts, or dark spices. And while light roasts have marginally more caffeine than dark roasts, you can eliminate this issue by weighing your beans instead of scooping them! Ultimately, it all comes down to your flavour preferences and the qualities you're looking for in a cup of coffee.