11th of May 2018
Do you choose the light side or the dark side? It’s an eternal question for coffee aficionados when it comes to roasting. For a start, it’s a matter of taste—literally. The level to which coffee beans are roasted is one of the main factors that determine the taste of the brewed coffee. Dark roasted coffees have a sheen of oil on their surface and the coffee will generally have a smoky and bitter taste. Light roast, by comparison, has no oil on their surface and a more toasted grain taste with a pronounced acidity. The origin flavours of the bean are retained to a greater extent than in darker roasts. But how do they vary when it comes to health benefits? And which is healthier: light roast or dark roast coffee?
For years the health benefits of coffee have been debated. While at one time too much coffee was thought to be bad for the heart, due to the fact that it slightly (and temporarily) increases blood pressure, it is now widely seen as having several major health benefits. One of the most documented of these benefits is the antioxidant qualities associated with our favourite morning pick-me-up. A recent study from the Journal of Medicinal Food from Korea has sought to determine which roasting method produces the healthiest cup of coffee and why?
The team of researchers analysed all the varying factors in different styles of roast, including their caffeine levels, the content of chlorogenic acid, which is known to be an effective antioxidant and their anti-inflammatory qualities. The study focused on Arabica coffee beans roasted in the light, medium, “city,” and French styles. These beans were ground and run through an espresso machine to obtain the test extract. So what were their findings?
Let’s start with caffeine levels. The Journal of Medicinal Food’s study suggested that there isn’t a noticeable difference in the caffeine levels of dark roast or light roasted coffee. In fact, in spite of the common misconception that dark roasted coffee has higher caffeine content, in part, due to its stronger flavour, the study found that energy-boosting compound didn’t fluctuate significantly with either roast style.
But, they discovered, when it came to the levels of chlorogenic acid and antioxidant qualities there was a difference. The study’s results suggested that the lighter the coffee roast, the higher the chlorogenic acid content. This is significant in terms of the potential health benefits, as the lighter roast seem to offer higher antioxidant properties, making them better for the drinker. The study also found that light roast was better for protecting against inflammation and cell damage compared to its dark roast counterpart.
While these studies are in the early stages, and have still to be conclusively tested in longer-term scientific human trials, other food substance high in antioxidants have been known to protect against health problems; while those with strong anti-inflammation properties can protect against chronic diseases such as heart disease, cancer, diabetes and several major neurological diseases.
Part of the reason for the higher level of antioxidant in lighter roasts could be down to the lower temperature and shorter length of time the beans are roasted for, which would both contribute to higher the oxidation of the beans in lighter roasts. So it seems that while both dark roast and light roasts have health benefits, if you want to keep more of the nutritional value of the bean, light roasting is the way to go!