Good news for people who derive some sort of satisfaction from claiming that cold brew stinks (and bad news for literally everyone else): science seems to show that hot coffee is better for you. A new study published recently in Scientific Reports titled Acidity and Antioxidant Activity of Cold Brew Coffee finds that hot brewed coffee is similar in pH and higher in antioxidants than the cold brewed version of the same coffee.
As reported by Health.com, the study was co-authored by assistant and associate professors of chemistry at Thomas Jefferson University Dr. Megan Fuller and Dr. Niny Rao, respectively. Using five different commercially available pre-ground coffees—Ethiopia Ardi, Ethiopia YirgZ (shout out to Keffa Coffee), Brazil, Colombia, and Myanmar—between a light and medium roast, the researchers brewed hot and cold coffees using the “same ratio of water volume to grind weight,” per the study.
Fuller and Rao (but not that Rao) found that, ostensibly contrary to general sentiment that cold brew is less acidic than hot coffee, the two had similar pH’s: cold brew ranging from 4.96 to 5.13 (YirgZ being the lowest and Myanmar the highest) and hot coffee 4.85 to 5.10 (Ardi and Brazil). However, the go on to note that hot coffee contained “larger measures of titratable acidity, indicating higher concentrations of extracted acids and/or additional acidic compounds not found in the cold brew,” and that it is this acidic complexity in hot coffee that may be the cause (or be a better indicator than pH) of the higher acidity, perceived or actual.
In terms of antioxidant activity, the thing associated with most of coffee’s health benefits, hot coffee was found to have higher concentrations of total caffeoylquinic acids (CQAs). CQAs are believed to play a significant role in coffee’s antioxidative benefits, and indeed this study finds higher antioxidant activity in hot coffee than cold brew. But it also found that while CQAs were a good indicator of antioxidant activity in cold brew, it was less so in hot coffee. This means that, as Fuller and Rao put it in the most badass way imaginable, hot coffee may also have “additional radical-scavenging compounds” that are boosting the antioxidant activity.
Now, seeing how I can't let the anti-cold brew bad guys win, let me grasp at a few straws here. Without any sort of TDS reading, we don't know that these coffees were comparably extracted and perhaps this leads to the lower antioxidant levels in cold brew. Perhaps grind size played a factor; the same grind is presumably not ideal for both brew methods, which may contribute to the results.
I dunno, I'm not a scientists, I'm just a guy who doesn't really drink cold brew that will fight for you right to do so unshamed. And so what? Maybe hot coffee has more antioxidant activity. Nothing a handful of blueberries can’t make up for.