A new study has found that antioxidant levels are higher in hot brew coffee than cold brew. The researchers, from Jefferson (Philadelphia University + Thomas Jefferson University), say the difference may have health impacts.
Scientists believe that antioxidants are responsible for some of coffee’s health benefits.
Niny Z. Rao and Megan Fuller wrote about their study and findings in the journal Scientific Reports (citation below). They both work at Jefferson’s Department of Chemistry.
Cold brew is a no-heat long-steeping way of preparing coffee.
Cold brew vs. hot brew coffee – pH levels
The researchers also found that both cold and hot brew coffee have similar pH levels. Among all the coffee samples they tested, pH levels ranged from 4.85 to 5.13.
Lifestyle blogs and coffee companies often tout cold brew coffee as being less acidic than hot coffee. They suggest that because of this, cold brew coffee is less likely to cause gastrointestinal problems. Heartburn, for example, is a gastrointestinal problem.
If their pH levels are similar, however, coffee drinkers need to know that cold coffee does not help avoid gastrointestinal distress.
Popularity of cold brew coffee
Over a five year period – 2011 to 2016 – the market for cold brew coffee in the US grew by 580 percent.
Despite its growing popularity, the researchers found almost no studies on cold brew.
There have been many studies, on the other hand, on hot brew coffee. Some of them showed that hot brew coffee has measurable health benefits including a lower risk of depression and diabetes. There is also documented research suggesting that it helps reduce the risk of developing some cancers.
Hot brew has more total titratable acids
Even though overall pH levels were fairly similar, the authors found that hot brew coffee had more total titratable acids. They also suggested that the greater titratable acid levels were responsible for the higher antioxidant levels.
Regarding the antioxidant capacity of hot brew coffee, Fuller said:
“Coffee has a lot of antioxidants, if you drink it in moderation, research shows it can be pretty good for you. We found the hot brew has more antioxidant capacity.”
Coffee drinkers should not consider cold brew coffee a ‘silver bullet’ for avoiding gastrointestinal problems, Rao added, given that they have comparable pH levels.
“Acidity and Antioxidant Activity of Cold Brew Coffee,” Niny Z. Rao and Megan Fuller. Scientific Reports, Volume 8, Article number: 16030 (2018). DOI: https://doi.org/10.1038/s41598-018-34392-w.