What do taste buds detect to perceive sourness in a beverage?

Taste buds perceive sourness primarily through the detection of hydrogen ions. When acid-containing substances are consumed, they release hydrogen ions into the solution, which interact with specific receptors on the taste buds. This interaction triggers the neural pathways that signal the brain to interpret the flavor as sour.

Acids, such as citric acid in lemons or lactic acid in yogurt, enhance the perception of sourness due to the presence of these hydrogen ions. This mechanism is a vital aspect of how we experience and interpret different flavors, distinguishing them from other tastes like sweet or salty.

The other choices involve different compounds that are not primarily responsible for the sour taste perception. Fatty acids contribute to the taste of fat, amino acids can impart umami flavors, and carbohydrates are linked to sweetness rather than sourness.