According to a new study published in the journal Scientific Reports, the hot brew method extracts more antioxidants from coffee than the cold brew method.

Cold brew coffee — made through a low-temperature, long-contact brewing method — is a popular phenomenon that has recently invigorated the coffee industry, particularly in the warm summer months.

Despite the growing popularity of cold brew (the U.S. market grew 580% from 2011 to 2016), very little research has been made on its chemical attributes, including pH and total antioxidant activity, and associated health effects.

At the same time, there is well-documented research that hot-brewed coffee has some measurable health benefits, including lower risk of some cancers, diabetes and depression.

“Coffee has a lot of antioxidants, and if you drink it in moderation, research shows it can be pretty good for you,” said study co-author Dr. Megan Fuller, a researcher in the Department of Chemistry and Biochemistry at Thomas Jefferson University.

In the study, Dr. Fuller and her colleague, Dr. Niny Rao, analyzed the acidity and antioxidant activity of cold brew coffee using light roast coffees from Brazil, two regions of Ethiopia, Columbia, Myanmar, and Mexico.

The scientists then compared cold brew coffee chemistry to that of hot brew prepared with the same grind-to-coffee ratio.

They found that hot-brewed coffee had more total titratable acids, which are believed to be responsible for the hot cup’s higher antioxidant levels.

They also found that the pH levels of both hot and cold coffee were similar, ranging from 4.85 to 5.13 for all coffee samples tested.

“Considering hot and cold brews have comparable pH levels, coffee drinkers should not consider cold brew a ‘silver bullet’ for avoiding gastrointestinal distress,” Dr. Rao said.

_____

Niny Z. Rao & Megan Fuller. 2018. Acidity and Antioxidant Activity of Cold Brew Coffee. Scientific Reports 8, article number: 16030; doi: 10.1038/s41598-018-34392-w