Why can cinnamon create a burning sensation in the mouth?

Answer: Its aromatic compounds activate irritation-sensing nerves

Its aromatic compounds activate irritation-sensing nerves ✓ — Cinnamaldehyde, an aromatic compound in cinnamon, activates TRPA1 channels in sensory nerves. Those nerves signal irritation and burning. The sensation does not require the cinnamon to be physically hot.

Its sugar heats up as soon as it dissolves in saliva — Dissolving cinnamon’s sugar is not what causes its characteristic burn. A food can feel hot because it activates sensory nerves, without becoming physically hotter.

Its acids are what produce the characteristic spicy burn — Acidity is not the mechanism that explains cinnamon’s characteristic pungency. Cinnamaldehyde activates irritation-sensing nerve channels rather than producing the sensation simply through acid.