Long-term stability of thujone, fenchone, and pinocamphone in vintage preban absinthe.

Research was conducted to ascertain whether analyses of vintage absinthe samples represent their original composition in the early 1900s. Absinthe stored in traditional green glass bottles and irradiated with ultraviolet light for up to 200 h exhibited unchanged composition. Samples stored in clear glass exhibited an 18% reduction in beta-thujone content and a concurrent decoloration.

Chemical composition of vintage preban absinthe with special reference to thujone, fenchone, pinocamphone, methanol, copper, and antimony concentrations.

Thirteen samples of authentic absinthe dating from the preban era (i.e., prior to 1915) were analyzed for parameters that were hypothesized as contributing to the toxicity of the spirit, including naturally occurring herbal essences (thujone, pinocamphone, fenchone), methanol, higher alcohols, copper, and antimony.