Whether you choose to drink your coffee cold brewed or hot brewed, the method makes a difference not only in taste but in antioxidants, acidity, and its chemical profile.
Cold brew coffee is made when ground coffee is steeped in cold or room temperature water for about 2 days. The process can be done with or without refrigeration. In contrast, the brewing method for hot brew coffee involves boiling water and steeping for a few minutes. The coffee grounds from either method are discarded and the remaining fluid filtered to remove excess coffee grounds.
To study what the effects of different brewing temperatures made to coffee, researchers at Thomas Jefferson University examined the constituent profiles of coffee beans which were roasted at different temperatures before cold or hot brewing. Coffee-lovers will be glad to hear that caffeine content stays consistent between hot and cold brewing methods!
A big difference between hot and cold brewed coffee is in the antioxidants. Hot brewing gives you higher amounts of antioxidants; and the darker the roast on the coffee bean, the more the antioxidants are released. Hot brewing contains more acids than cold brewing, but the darker roasts of the coffee bean decrease acidity as you go darker.
Despite changes in actual acidity, the pH is roast-darkness dependent whether you choose cold or hot brewing. The takeaway is that the difference in brewing temperature will result in either less or more antioxidants, and the degree of roasting for the bean will impact acidity and give you more antioxidants. The researchers have planned future studies to examine other constituents of coffee.
Do you want to try cold brew coffee but aren't sure how to do it? This cold brew coffee pitcher fits right in your fridge. Some regular hot coffee drip machines now also have cold brew options built in that can give you a cold brew in just 10 minutes! But for those of you who love your ready-made cold brew, check out this cold brew-on-tap-in-a-box.
Have you wondered why cold brew coffee doesn’t smell like its hot brewed counterpart? The compounds inside the coffee which produce the aroma are still there, but the cold brew doesn’t have any steam to release them into the air.
Grim, Megham D., et al. “Role of Roast on Chemical Characteristics of Cold Brew Coffee.” American Chemical Society Spring 2020 National Meeting & Expo, 1 Apr. 2020.