Reading Coffee Flavor with Electrical Signals... Technology Emerges to Quantify Taste

University of Oregon Research Team Develops Electrochemical Coffee Analysis
Quantifying Flavor Without Complex Equipment or Tasting
"Enabling Quality Control and Industrial Applications"

A new technology has been developed that analyzes the concentration and roasting level—factors influencing the flavor—of coffee extracted from beans as electrical signals, enabling the realization of consistent taste.

Three electrochemical electrodes analyzing the components of espresso coffee. Research team from the University of Oregon, USA

According to Yonhap News on April 29, a research team from the University of Oregon in the United States announced in the scientific journal 'Nature Communications' that they have developed a method for quantifying coffee flavor profiles by inserting three electrodes into coffee, running a current, and analyzing the resulting electrochemical reactions.

Professor Christopher Hendon, who led the research, stated, "The taste of coffee is determined by 'roastiness,' which is the result of the combination of concentration and degree (color) of roasting." He added, "The goal of our research is to achieve a more consistent taste while still reflecting individual preferences."

Coffee flavor is known to be affected by a variety of variables—including the type and amount of beans, roasting level, grind size, and water temperature—so even small changes in the process can lead to significant differences in taste, making consistency difficult to maintain. Currently, professional tasting or measuring the concentration of total dissolved solids (TDS) using refractometry are mainly used, but it is hard to distinguish chemical differences and flavor profiles caused by roasting or extraction conditions based on concentration alone.

The research team objectively measured coffee flavor elements using a potentiostat, an electrochemical analysis device sensitive to chemical composition changes. This device analyzes the characteristics of molecules in the solution via cyclic voltammetry, in which three electrodes are inserted into the coffee and voltage is applied to measure changes in current—without any preprocessing.

The experiments revealed a clear proportional relationship between coffee concentration and the total charge measured by the electrodes. As the concentration increased, the current signal became stronger, which was attributed to a greater number of molecules participating in the reaction due to increased acidic substances and dissolved components. Conversely, at the same concentration, the current signal decreased as the degree of roasting intensified. This was because organic compounds, such as caffeine, altered during roasting, adsorbed onto the platinum electrode surface and suppressed the reaction.

The research team explained, "With this method, we were able to identify a unique chemical fingerprint for each coffee, allowing for a more precise quantification of flavor." They added, "Since the electrical signals clearly differ depending on the type of beans and extraction method, baristas can use this technique to set and consistently reproduce their desired flavor profiles." In fact, when tested at a roastery in the United Kingdom with four samples that could not be distinguished by appearance, the electrochemical method accurately identified those that did not meet quality standards.

Professor Hendon said, "This method enables people to objectively describe the elements they prefer in a cup of coffee." He continued, "A good flavor results from extracting beans with a particular roasting color at the desired concentration, and now we can identify the causes of that flavor." He also emphasized, "This technology is one of the first methods capable of quantitatively evaluating coffee concentration and roasting level separately. It can be used not only for quality control, but also for optimizing blending and analyzing batch-to-batch differences, making it applicable in a wide range of industrial contexts."

This content was produced with the assistance of AI translation services.