(+)-(2R)-Furaneol® - obviously strong, sugary, jammy, sweet Flavor threshold = 60 ppb (for the racemate) Odor threshold = 1 - 4 ppb (in air for the racemate) = (+)-(2R)-2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) Ref: Yoshihiro Yaguchi, Atsufumi Nakahashi, Nobuaki Miura, Daisuke Sugimoto, Kenji Monde, and Makoto Emura, Stereochemical Study of Chiral Tautomeric Flavorous Furanones by Vibrational Circular Dichroism, Org. Lett., ASAP Article, 10.1021/ol801966t, Web Release Date: September 26, 2008; Makoto Emura, Yoshihiro Yaguchi, Atsufumi Nakahashi, Daisuke Sugimoto, Nobuaki Miura and Kenji Monde, Stereochemical Studies of Odorous 2-Substituted-3(2H)-furanones by Vibrational Circular Dichroism, J. Agric. Food Chem., 2009, 57 (21), pp 9909–9915 For threshold in air see SCHIEBERLE, P. & W. GROSCH (1994), Potent odorants of rye bread crust ? differences from the crumb and from wheat bread crust, Z. Lebensm. Unters. Forsch., 198, 292?296 Furaneol® is a registered trademark of Firmenich SA

(-)-(2S)-Furaneol® - extremely weak Flavor threshold = 60 ppb (for the racemate) Odor threshold = 1 - 4 ppb (in air for the racemate) = (-)-(2S)-2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) Ref: Yoshihiro Yaguchi, Atsufumi Nakahashi, Nobuaki Miura, Daisuke Sugimoto, Kenji Monde, and Makoto Emura, Stereochemical Study of Chiral Tautomeric Flavorous Furanones by Vibrational Circular Dichroism, Org. Lett., ASAP Article, 10.1021/ol801966t, Web Release Date: September 26, 2008; Org.Lett. 2008, 10, 4883–4885; Makoto Emura, Yoshihiro Yaguchi, Atsufumi Nakahashi, Daisuke Sugimoto, Nobuaki Miura and Kenji Monde, Stereochemical Studies of Odorous 2-Substituted-3(2H)-furanones by Vibrational Circular Dichroism, J. Agric. Food Chem., 2009, 57 (21), pp 9909–9915 Furaneol® is a registered trademark of Firmenich SA

Ionones, Irones, Damascones & Structurally Related Odorants

Acyclics (Alcohols, Esters, Acids, Aldehydes)

Lactones & Furanones

Sesquiterpenoid Related Odorants