Cold brew coffee consumption has skyrocketed, with its market growth soaring 580 percent from 2011 to 2016. Despite its popularity, scientists have published little research on the chemistry of cold brew coffee, which is made through a low-temperature, long-contact brewing method where grinds are soaked with room temperature water for eight to 24 hours.
University investigators plan to explore relatively uncharted territory, with the help from a sizable grant from the United States Department of Agriculture’s National Institute of Food and Agriculture.
Project director Niny Rao, PhD, associate professor of chemistry, along with Megan Fuller, PhD, assistant professor of chemistry, and Frank Wilkinson, PhD, associate professor of biochemistry, have received $93,780 to establish a foundational understanding of some key chemical metrics of both traditional and nitro-infused cold brew coffees. Nitro-cold brew coffee—a boutique cold brew beverage infused with nitrogen—has a mouthfeel similar to some craft beers. However, the introduction of nitrogen creates an anaerobic environment conducive to botulin toxin development.
The Jefferson (Philadelphia University + Thomas Jefferson University) investigators will measure total acidity, pH, chlorogenic acid and caffeine concentrations, antioxidant capacity and flavor for cold brew coffee extracts using three types of roasts.
“The immediate output of this project is to expand the understanding of cold brew coffee chemistry, including the survivability of spoilage microorganisms,” said Dr. Rao, noting she hopes their research will educate coffee drinkers and aid health officials to develop food safety inspection protocols. “The ultimate goal is to improve best practice standards in the cold brew coffee industry to provide a better and safer experience to all consumers.”
Last year, Scientific Reports published Drs. Rao and Fuller’s research that found the hot brew method produced higher levels of antioxidants in coffee than the cold brew method.