How Much Caffeine is in a Cup of Dilworth Coffee?

Is this a trick question? Caffeine content can depend on how the coffee is roasted, how it is brewed, and even the varietal of the coffee.

Roast level is an often misunderstood variable when it comes to caffeine content. Some say dark roast should have more caffeine because it tastes stronger, while others claim light roast must have the highest content since it is roasted less and therefore has lost less of its original green bean weight in the roaster.

The first thing to know is that caffeine is a very stable molecule that does not easily break down during the roasting process. We also know that dark roasts lose more of their original green bean weight during roasting. Since caffeine is stable and is not part of what is lost, that caffeine will make up a greater percentage of the post roast weight of that bean. Therefore, dark roasts will have more caffeine per bean. Not by much though and in fact, few coffee drinkers are likely to perceive the difference.

A factor that can be more perceivable is the type of brewing method involved, specifically the brewing time. For example, an 8oz americano will have less caffeine than an 8oz cup of batch brew. That is because the americano (2oz espresso shot diluted with 6oz of water) will have been brewed for a relatively short amount of time (generally around 30 sec per shot) and is then diluted with 6oz of water. A batch brew will take much longer (generally 4-6 mins per batch). Since we know that the longer we steep a particle of ground coffee, the more of its soluble molecules will be dissolved (including caffeine), we can accurately say that more caffeine will be present in the final cup of batch brew.

Temperature also plays an important role. Even though cold brew is steeped for 18-24 hours, it will end up with caffeine content generally in line with batch brewed. This is because the extraction of caffeine is inhibited by the lack of kinetic energy in the “colder” brewing water.

Another factor can be the species of coffee in question. The Robusta species has roughly twice the caffeine content of Arabica coffees. Caffeine is bitter tasting which typically causes Robusta to present with a much more bitter cup profile that most coffee lovers dislike. (Disclaimer: We currently do not offer any Robusta coffees at Dilworth Coffee.)

With all this said, a cup of Arabica batch brew (or cold brew) should have somewhere between 95-175mg of caffeine per 8oz cup depending on the variables described above. The americano should have around half the caffeine per 8oz cup.

Whichever brew you choose, fill it how you feel it.