Factors that Influence Caffeine Levels in Coffee

As coffee lovers, we love a caffeine kick to get the day started. But we don’t want to end up with a queasy stomach or having to deal with heart palpitations from an overly-caffeinated cup of coffee…or drift off to sleep in the middle of a meeting because we’re under-caffeinated.

Not sure what it takes to get that perfect amount of caffeine? Here are factors that influence the caffeine levels in your coffee.

Type of Coffee Bean

Boxes of coffee beans being retailed
Various types of coffee beans contain different levels of caffeine. Photo from Pauline Bernfeld.

There are many species of the coffee plant, and different types of coffee grow best at various parts of the world. Due to unique growing conditions which affect the bean’s characteristics, coffee beans from different plants will vary in their caffeine content.

Coffee plants have a natural ability to produce caffeine as a pesticide. At higher altitudes, these plants produce less caffeine as the presence of pesticides are lesser than at lower altitudes.

Take for instance, the world’s most popular coffee bean, Arabica and its well-known counterpart, Robusta. Arabica grows best at around 1,300 – 1,500m, whereas Robusta grows at a maximum altitude of 600m. As a result, Arabica has a much lower caffeine level than the Robusta.

Coffee Bean Roasting Time

Always thought that the darker the roast, the stronger the caffeine kick will be? That’s a common misconception. The caffeine level of the coffee remains relatively constant during the roasting process.

The longer the roasting time, the less dense a coffee bean will be as coffee expands during roasting and loses water weight. This means in a single scoop of coffee grounds, there are more dark coffee grounds than light coffee grounds. That is why darker roasts tend to taste richer and more robust as you are using more coffee grounds.

Grind Size

a person tamping coffee grounds
Grind size will affect the surface area that the grounds are exposed to water. Photo from Noora AlHammadi.

Grind size will greatly affect the coffee you brew as it exposes the flavours and aromatics that are locked in the coffee bean. The finer the grind, the higher the surface area that the grounds are exposed to water. With greater exposure, the more caffeine will be extracted.

Always ensure that your coffee beans are ground to a size that is perfect for your brewing equipment. This prevents over- and under-extraction – a mistake that can be easily avoided. Refer to this infographic to find out which grind size is best for your brewing method.

Brewing Time

Various brewing methods will require different brewing times. The longer the coffee grounds are in contact with water, the higher the caffeine concentration.

For instance, the French Press method involves the constant infusion of coffee grounds in water for 2-4 minutes. Undoubtedly, the caffeine level is much higher than drip coffee which requires less time.

To get the perfect caffeine extraction, here’s a guide on how long you should be brewing your coffee for 5 of the most popular types of coffee makers.

Brewing Method

a person pressing a button on a coffee machine
Best-in-technology coffee machines offer the possibility to customise your beverages based on your preferences. Featuring the De’Longhi Maestosa Fully Automatic Coffee Machine. Photo from De’Longhi.

With each brewing method, variables such as the ratio of water to coffee grounds as well as the brewing technique will affect the caffeine content.

If you don’t want to worry about which brewing method is best for your preferred caffeine strength, we have a solution. Whether you like a stronger cup today, or a lighter one tomorrow, these machines give you endless possibilities to customise your coffee.