Science Snapshots: May 3, 2026

Electric method can identify coffee strength and roast

The industry’s current tools can measure coffee strength but can’t separate roast colours. Researchers used cyclic voltammetry to pass a current through brewed coffee and found the electrical response revealed the strength. They also found the roast colour was related to how much caffeine stuck to the electrode and blocked the current. The team used the method to spot a bad batch of coffee a roaster had rejected while extant tools couldn’t detect the flaw.