Coffee is the indispensable beverage for millions of people around the world. As we know, its high caffeine content is an important part of why some people drink it.
However, there are many misconceptions regarding the caffeine levels found in different types of coffee drinks. Cold brew is no exception. At the same time, this icy, refreshing drink is fast becoming more popular around the world.
Read on to better understand how much caffeine is in cold brew and how it's measured against other brewing methods.
How to make cold brew?
While most consumers are familiar with iced coffee (brewed coffee served over ice), there is another cold beverage that offers a completely different sensory experience: cold brew.
Cold brew is coffee brewed with cold water, exactly as the name suggests. There are two main methods for doing this: dipping and Kyoto cold dripping.
With immersion, coffee is brewed in cold or room temperature water for 18 to 24 hours. Coffee can be left to stand on a counter or in the refrigerator. After the brewing process is complete, the grounds are filtered.
The Kyoto cold drip method is slightly different. In this case, water is slowly dripped from a coffee bed over two to six hours.
Cold brew is also a flexible brewing method. It allows the user to experiment by adjusting variables such as coffee source, grind size and brewing time until they find the perfect cup for them.
Ultimately, this not only makes the drink versatile, but also gives it a smooth flavor and makes it suitable for warmer climates. Because of this, it has become incredibly popular in specialty coffee shops around the world and as a ready-to-drink (RTD) beverage.
Beyond that, the fact that it's so easy to make in the comfort of a kitchen has made it popular with home consumers as well.
Cold brew is typically made from a concentrate and is usually served over ice. It is light, sweet and smooth with minimal bitterness and acidity. It serves as an excellent base for cocktails and other cold coffee drinks. 
Caffeine levels in cold brew
According to the National Coffee Association, one in five Americans under the age of 40 consumes at least one serving of cold brew per week. Naturally, this growing market wants to know exactly how much caffeine is in their drinks.
Raymond Buerger is the founder and CEO of Brew Bomb, a manufacturer of cold brew equipment from Colorado, USA. He explains how caffeine levels in coffee vary depending on a number of factors.
"The key to caffeine content is to look at how caffeine is formed," says Raymond. “Caffeine is produced by the coffee plant as a natural pesticide to provide a defense against insects.
"We all know that different cultivars, [species] and growing climates affect the taste experience of coffee, so it makes sense that these variables also affect caffeine levels."
However, caffeine content is primarily determined by species, more than any other factor. Robusta coffee beans contain almost twice as much caffeine as Arabica.
But what about the rest of the coffee supply chain beyond production? What about roasting? Do darker fries have more caffeine?
Matt Swenson is Director of Coffee at Nestle Partners. He says the roasting process does not break down the caffeine, which makes it safe to assume that the roast profile has a negligible effect on the amount of caffeine in the final cup.
Raymond agrees: "Caffeine survives the temperature changes affected by roasting, so the amount of caffeine available is the same across all roast profiles.
"But roasting affects the cell structure of the bean, making it easier to remove soluble substances in dark roasts."
As you can imagine, another important factor in the brewing process is the ratio of coffee to water.
"Assuming the cold brew is 100% Arabica, the biggest variable in caffeine content in cold brew is the concentration of the finished product," says Matt. "We define it as the total amount of dissolved solids (TDS) in the beverage."
As a result, the caffeine content of cold brew is determined by the brew rate and concentration, not the roasting profile or processing method of the beans used.
What about other brewing methods?
Now that we understand some of the factors that affect caffeine content, let's explore exactly how much caffeine is in cold brew compared to other brewing methods.
First of all, any cold brew method will typically produce coffee with slightly higher caffeine levels than those made with percolation methods (bulk or batch brew).
However, while the longer brew time theoretically gives the water much more time to extract the caffeine from your beans, it's comparable to other brewing methods in terms of caffeine content.
"Cold brew is often said to contain more caffeine than other brewing methods, but this is not always the case," explains Matt. "It's not the brewing method that ultimately makes this difference in caffeine, but the strength with which the beverage is served."
While cold brew can contain 10 to 30 percent more total dissolved solids than brewed filter coffee, it's usually diluted before serving, she says. This significantly lowers the caffeine concentration.
Matt also notes that there is a "declining point of return" for caffeine extraction. Once cold brew reaches this saturation point, no amount of brewing time can increase caffeine extraction. In essence, a longer brew time after a certain point does not guarantee more caffeine.
Ray adds: “For hot brew methods, 90% of available caffeine extracts are released in 5 minutes 54 seconds. For cold water extraction, the caffeine content is rapidly extracted within the first 180 minutes and then reaches plateaus, as shown by research by Fuller and Rao.
"Given the ease of caffeine extraction, the brewing method is not a major factor in the final caffeine content in cold brew."
As a result, the caffeine content is more dependent on how concentrated a beverage is and less on the brewing time.
This makes it possible for different cafes to offer cold brew drinks with different levels of caffeine – so if you're looking for a cold brew that better suits your tastes, don't be afraid to shop around.
Consumer perception of how much caffeine is in cold brew
As with espresso, many consumers believe cold brew is particularly high in caffeine. Many people shy away from cold brew for this reason, although it may be a bit of a misconception.
"Generally speaking, this [perception] is true, but it's not necessarily because the caffeine is removed during the brewing process," says Matt. "Instead, the coffee/caffeine concentration during serving."
Ray explains that because of this misconception, new consumers will quickly run away, especially if they actually try concentrated cold brew.
She says: “This is why we find that many roasters choose their origin carefully and use lower final concentrations to control the caffeine content of cold brew offerings.
Cold brew is a staple beverage that is growing rapidly and quickly becoming popular with specialty coffee consumers worldwide. While concentrated cold-brew drinks may contain slightly more caffeine than other beverages, it's not the brewing method itself that causes it.
Despite any misconceptions about its caffeine content, cold brew continues to gain momentum in a variety of markets, including young and millennial consumers. It is one of the fastest growing coffee beverages in consumption statistics, with an average annual increase of 4.6%.
This shows how popular cold brew coffee is, whether for its caffeine content or not. Looking for something new? Maybe you should try making some at home!
