Coffee

Does cold brew have more caffeine?

Royal New York specialty cold brewed coffee

Cold brewed coffee and tea have become increasingly popular in recent years. With its rise in popularity, there has been a flood of mixed information on the caffeine content of cold brew. We sought out to answer the question, does cold brew have more caffeine?

What is cold brew?

First, for those who don’t know, cold brewing is a method of extracting coffee or tea into cold water rather than hot. For coffee, it is typically brewed using a 1:5 – 1:10 grams to mL ratio of course ground coffee to water. For tea, it is brewed using 2 – 3 oz of loose leaf tea per gallon of water. Both coffee and tea is cold brewed over an 8-12 hour period in a refrigerated environment. The cold-water extraction allows for a different set of compounds to be extracted from the coffee and tea than hot brewing. One of these compounds is, you guessed it, caffeine!

Caffeine extraction in hot and cold brewed coffee

While caffeine is extracted in both hot and cold brewed coffee, it does extract differently. Caffeine extraction in coffee is dependent on multiple factors. Grind size, water temperature, roast profile, extraction method, and brew time will all ultimately determine how much caffeine ends up in your coffee.

A study in April 2014 found that caffeine’s solubility into water increases significantly as water temperature increases. In fact, the level of solubility in water at 25 (C) is only about 2%. Whereas the level of solubility in 100 (C) (or boiling point) is 66.7%. Considering these facts, the temperature clearly makes a pretty drastic difference.

Does cold brew coffee have more caffeine?

However, hot coffee obviously doesn’t have 33x more caffeine than cold brew. So, we have to look at other contributing factors for the answer. A study in October of 2017 found an average concentration of caffeine content in a 355ml (12oz) volume of water to be 207mg brewed at 4 (C). Comparatively, a cup of hot coffee has about 150mg of caffeine per 12oz serving. So, why does cold brew coffee have more caffeine than hot coffee if the rate of solubility is higher?

The difference is primarily in the brew time. While it only takes a few minutes to brew a cup of hot coffee, you don’t want to be drinking cold brew that’s only been steeped for that short of a period using a traditional brew method.  In order to make a cold brew that actually tastes good using a traditional brew method, you’ll need 8-12 hours, although there are products on the market that are capable of producing cold brewed coffee in a significantly shorter period of time. In that time, caffeine has plenty of time to dissolve into the cold water coffee it’s steeped in. Despite caffeine extracting more efficiently in hot water, the extended brew time does end up allowing the caffeine content in cold brew to eclipse that of a hot drip coffee. On top of that, it also requires about twice as much coffee to brew cold brew than it does to brew hot coffee. So next time you’re feeling a little jittery from a cup of cold brew, you’ll know why!

But what about cold brewed tea?

When it comes to tea, all camellia sinensis (black, green, white, oolong, puer, yellow, and purple tea) and blends including the tea plant will have caffeine.  Tisanes, or herbal blends that do not contain camellia sinensis, typically are caffeine free. However, there are some exceptions.  Yerba mate, a holly plant native to South America, and its North American cousin yaupon are two such examples.  Cocoa also naturally contains caffeine.

As with any caffeinated plant, a wide array of influences effect level of caffeine in tea.  Species, variety/cultivar, terroir, climate, soil content, and processing are just a few of the factors that impact how much caffeine is present by the time the tea is ready to brew.  Lower caffeine pure teas can have as little as 10mg of caffeine per serving. Teas with higher content can exceed 100mg. 

Generally speaking, green and white teas will have lower caffeine while black and puer teas will have higher caffeine. But again, there are plenty of exceptions!  When yerba mate is prepared in the traditional manner it can even exceed the amount of caffeine in coffee!

Does cold brew tea have more caffeine?

Caffeine is soluble in hot and cold water but will extract more slowly at cooler temperatures.  The size of the tea leaf will also impact caffeine extraction.  Fannings and broken grades will steep faster and stronger than full leaf teas.  Though results can vary depending on the size and shape of the leaves, tea that is cold brewed typically has about half the caffeine of hot brewed tea when using the same volume of tea.

However, keep in mind that cold brew tea recipes call for a higher quantity of leaves compared to hot brewing.  Depending on the tea and the desired result, double to triple the amount of tea is needed.  We recommend using 2 to 3 ounces of tea per gallon when cold brewing, compared to about 1 ounce of tea per gallon of hot water.  While cold brewing may extract less caffeine, the increased volume of tea used will result in a drink with a similar level of caffeine to hot brewed.

One benefit of cold brewing is tannins are much less soluble at lower temperatures, so cold brewed tea will have much lower tannin content than their hot brewed counterparts.  Tannins typically taste bitter or astringent on the palate, so cold brewing tea can create a sweeter, smoother drink.  Cold brewing can also potentially be better for extracting beneficial antioxidants and phenolic compounds.

Ready to brew some cold brew coffee & tea?

Want to make some cold brew yourself? Check out some of our freshest coffee & tea arrivals we’re loving cold brewed!

Cold Brew Coffee

Organic Colombia Sierra Nevada Sol Naciente

Colombia Sierra Nevada Sol Naciente producer standing alongside his specialty coffee

Are you looking for a sweet and slightly fruity cold brew? Give our Organic Colombia Sierra Nevada Sol Naciente a try! This lot from Sol Naciente is juicy and bright. In the cup, we found notes of sweet stone fruit and citrus carried by a big chocolatey body.

Shop RNY # 53568

Honduras San Vicente SHG EP

washed coffee beans drying in Honduras

Are you looking for a rich chocolatey cold brew? Give our Honduras San Vicente SHG EP a try! This Honduran from Santa Barbara is big bodied and sweet. In the cup we found notes of rich caramel with smooth chocolate in the body.

Shop RNY # 53830

Cold Brew Tea

Golden Yunnan

Our Golden Yunnan is sweet and smooth with notes of dark chocolate, sweet potato, and caramel.  Cold brewing gives its natural sweetness a big boost!  We recommend to steep 3oz tea per gallon of cold water for about 6 hours.

Shop Golden Yunnan

Raspberry Elderflower Rosé

Royal Tea New York's Raspberry Elderflower Rosé cold brew tea

In spring and summer, fruity blends reign supreme on cold brew menus. Our spring seasonal herbal blend packs a flowery punch when cold brewed!  Elderflower’s cupping notes lean towards fruity pear and lychee.  We find that when this blend is cold brewed the elderflower shines brightest.

Shop Raspberry Elderflower Rosé

Notes:

For the purposes of this article, we’re exclusively taking about Arabica coffee since Robusta does have a higher caffeine content and a different set of data to go along with it.