As cold brew coffee has grown in popularity in recent years, so too has the number of strong opinions about the brewing method’s impact (positive or negative) on the flavors in the resulting cup—but they’d never been systematically studied.

There are countless coffee cuppings performed by coffee professionals around the world, assessing coffee quality, every day. Lead Author JIEXIN LIANG suggests we’re more easily able to control our total dissolved solids (TDS) via brew ratio instead of our extraction yield (E).

What could the color of your cold brew be communicating to your customers? Lead author SARA YEAGER shares the findings of a recently published paper, “Roast Level and Brew Temperature Significantly Affect the Color of Brewed Coffee,” published in the Journal of Food Science, exploring how coffee beverage color varies with origin, roast level, and brew temperature.

Brew temperature is widely considered to be one of these key variables affecting the final quality of coffee, with a temperature near 93°C believed by most to be best. And, while it is no surprise then that drip brewers that can’t reach 92°C fast enough fail their certification, it turns out there is little empirical (and even less scientific) evidence, however, to support any particular range of brew temperatures for optimal sensory quality and consumer acceptance.

Among all the factors that can impact coffee flavor, the brewing step specifically has been shown to impact sourness. Did you know that about half of consumers in a recent study prefer more acidity in their coffee, and about half prefer less?