In detail

Resveratrol exists as trans and cis isomers. The trans form is the one usually associated with the ingredient's research and premium positioning. A certificate that reports 'resveratrol 98%' without distinguishing the isomers leaves an important question open.

Isomerization can occur during processing and storage, especially with heat and light. The botanical source also matters: Japanese knotweed root and grape skin are different raw materials and different label stories. Ask for the trans share, the source, and the storage recommendation.

Why it matters to a buyer

  • Trans and cis are different molecules with different commercial positioning.
  • Isomer conversion during storage can reduce the trans share after release.
  • Source claims need to be documented, not inferred from the name.

What to ask a supplier

01

Is the 98% figure trans-resveratrol specifically?

02

What is the botanical source, and is it declared on the COA?

03

What storage conditions protect the trans share?

Cite this page

Rainwood Botanical. "Trans-resveratrol." Botanical extract glossary, October 2026. https://ingredients.rainwoodbio.com/resources/glossary/trans-resveratrol/