Capsaicin vs Dihydrocapsaicin
Capsaicin (C₁₈H₂₇NO₃) and dihydrocapsaicin differ by a single double bond. That one bond changes how they bind TRPV1: capsaicin produces a sharp, fast-onset burn focused on the back of the throat; dihydrocapsaicin delivers a broader, slower heat across the whole palate.
Molecular difference
Capsaicin has an unsaturated acyl chain (one C=C double bond at position 6). Dihydrocapsaicin has a fully saturated chain. That's the only structural difference — one double bond — but it changes the molecule's shape, flexibility, and how it docks into the TRPV1 ion channel.
Heat character
Capsaicin: sharp, stinging, rapid onset, concentrated in the throat and back of the mouth. Dihydrocapsaicin: diffuse, warming, slower onset, spread across the tongue and lips. Pure capsaicin feels like a needle; pure dihydrocapsaicin feels like a wave.
Relative pungency
Both are rated at 16 million SHU in pure form, but their perceived heat differs. Capsaicin's faster receptor binding makes it feel hotter at the same concentration. Most pungency scales weight them equally, which is technically correct but experientially misleading.
Ratio in Scoville Splice specimens
The capsaicin fraction climbs from 40% (Verbal Warning) to 75% (D.N.R.) across the lineup. This shift from balanced capsaicinoid blend toward capsaicin dominance is what changes the character of the heat from 'slow build, full flavor' to 'instant, linear, relentless.'
Capsaicin
Capsaicin has an unsaturated acyl chain (one C=C double bond at position 6). Dihydrocapsaicin has a fully saturated chain.
Dihydrocapsaicin
That's the only structural difference — one double bond — but it changes the molecule's shape, flexibility, and how it docks into the TRPV1 ion channel..