Daniel Suh Teaches the Science of Hot and Cold Brewed Coffee
Don't be so quick to ditch hot brewed coffee for cold this summer. While there are pros and cons to both brewing methods, Daniel Suh says it all boils down to a matter of taste and what flavor experience you're looking to get out of you're coffee. While the grind of your coffee and even the water you use to brew it are perhaps more important, the temperature you brew at will pull out different flavors and even change the way you taste it.
Heather Hoch Daniel Suh of Provisions Coffee at his co-op office space in downtown Chandler.
Hold onto your hats--it's about to get a little technical in here.
See Also: How To Make Cold Brew Coffee
Daniel Suh of Provision Coffee wasn't always a coffee guy. The Phoenix-native studied at the University of Arizona with a double major in finance and entrepreneurship and a minor in biochemistry. While discussing coffee, he's liable to warn you, and even apologize, several times for his coffee geek-outs. He's worked as a barista in coffee bars across the country and teaches classes and workshops in conjunction with the SCAA, approaching coffee from a scientific background to help lend some credibility and facts to the industry.
Let me just start by saying, if you're looking to find out whether cold brewed or hot brewed coffee is better, Suh isn't the guy to ask. He sums that sentiment up in saying, "To drink coffee in just one way, to me, you're just limiting your own experience."
Where cold and hot brewed coffees differ most is the flavors they extract, which largely does have to do with chemical reactions due to water temperature. In other words, cold brewed coffees tend to be smoother in quality, pulling out richer, chocolate and caramel notes. Hot brewed coffees tend to be fuller bodied and more acidic in taste because hot water is a more effective catalyst for pulling out those acids.
Suh explains that traditionally hot brewed coffees only have about 1.15% coffee material after brewing, with the other nearly 99% just being water. Espresso shots, on the other hand, are closer to 10% coffee material. This has nothing to do with the caffeine level in either, though, but the intensity of flavor.
Courtesy of Coffee Snob The official coffee tasting flavor wheel.
While bright, acidic flavors (or as Suh calls them, "sparkly and lively") come easy the cappuccinos, the addition of milk can sometimes result in a "sour milk" flavor in certain instances. For more bitter espresso shots, Suh recommends treating the shot like a shot of whiskey, which is more commonly put on ice or mixed with water or sugar to make it more palatable.
While those intense flavor issues can arise with hot brewed coffees, especially espresso, cold brew can suffer from a consistency issue. Suh says it's nearly impossible to ensure consistent flavor extraction and intensity with cold brewed coffee. So when I was excited because my cold brew had different flavors every time I tried it, I was really just tasting inconsistency. Whether that's a bad thing, you can decide for yourself.