Alchemist WebPick Awarded by the webzine of ChemWeb.com Leffingwell & Associates Odor Properties & Molecular Visualization gamma-Lactones & Molecular Structures  gamma-Lactones and delta-lactones are important flavor and aroma constituents in many natural products. Although both chiral enantiomeric forms occur in nature, the "R" chiral forms tend to be predominant (especially as the alkyl chain length increases). In constructiing molecular models, we will show only the "R-" enantiomers (as shown below for gamma-decalactone as pictured by the Accelrys Discovery Studio Visualizer with the chiral monitor turned on).   gamma-Valeroactone or 4-methylbutanolide...C5H8O2 ............................. is a relatively weak flavor chemical that occurs in products such as Cocoa, Coffee, Honey, Peach, Virginia Tobacco, Wheat Bread. The odor is often described as sweet, hay-like, coumarinic. Odor Detection Threshold (in beer) = 10,000 ppb Sweet, hay-like, coumarinic odor and coconut taste. gamma-Hexalactone or 4-ethylbutanolide...C6H10O2 .............................. occurs in products such as Apricot, Burley Tobacco, Cocoa, Grape, Grape Brandy, Mango, Peach, Raspberry, Strawberry, Wheat Bread. Mosciano, et. al. (1992), have described the organoleptic properties as follows: Odor as "Sweet, creamy, lactonic, tobacco and coumarin-like with green coconut nuances" and taste as "Sweet, creamy, vanilla-like with green lactonic powdery nuances" at 75 ppm. Odor Detection Threshold (in water) = 1600 ppb Coumarin-like, sweet odor and taste; creamy note gamma-Heptalactone or 4-propylbutanolide...C7H12O2 .......................... occurs in products such as Beer, Licorice, Mango, Roasted Filbert, Papaya, Peach, Strawberry, Tea, Wine. Mosciano, et. al. (1992), have described the organoleptic properties as follows: Odor as " Sweet, coconut, coumarin, lactonic, creamy and powdery" and taste as "Sweet, lactonic, creamy, coconut and coumarin, with a milky and tobacco nuances" at 15 ppm. Odor Detection Threshold (in water) = 400 ppb Coconut, hay-like, coumarinic odor gamma-Octalactone or 4-butylbutanolide...C8H14O2 .......................... occurs in products such as Apricot, Blue Cheese, Butter, Cooked Chicken, Cooked Pork, Licorice, Milk, Raspberry, Roasted Barley, Roasted Filbert (Hazelnut), Roasted Peanut, Roasted Pecan, Strawberry, Tea. Mosciano, et. al. report that this material has a "sweet, creamy dairy with fatty and oily coconut nuances" odor and a "sweet creamy, with coconut nuances" flavor at 50 ppm. Odor Detection Threshold (in water) = 7 ppb Sweet-coumarinic, coconut-like odor and taste gamma-Nonalactone or 4-pentylbutanolide...C9H16O2 .......................... This material is often referred to as "Aldehyde C-18 (so-called)" by perfumers and flavorists, but it, of course, is really a lactone, not an aldehyde. It occurs in products such as Asparagus, Beer, Cooked Pork, Licorice, Mushroom, Peach, Roasted Barley, Roasted Filbert, Tamarind, Tea, Virginia Tobacco, Wheat Bread, Whiskey, Wine. The odor of this material is very familiar because it has been used as the sole "coconut" fragrance material in certain very popular "Hawaiian" type sunscreen lotions. It is the basic characterizing flavor component in Artificial Coconut flavors. Interestingly, this material does not (to this authors knowledge) occur in coconut although the corresponding C-10 and C-12 lactones are present. Odor Detection Threshold (in water) = 65 ppb Strong, fatty, coconut odor and taste gamma-Decalactone or 4-hexylbutanolide...C10H18O2 .......................... occurs in products such as Apricot, Blue Cheese, Butter, Coconut milk (fresh), Guava, Mango, Oriental Tobacco, Peach, Plum, Strawberry, Tea, Wine. Mosciano, et. al. report that this material has a "fatty, creamy, coconut, buttery, vanilla sweet" odor and a "fatty, oily, coconut, buttery sweet" taste at 10 ppm. Mosciano, et. al. also report that this material has a "fruity, peach, with a sweet creamy character" odor and a "creamy, buttery, sweet, fruity peach like" taste at 1 ppm. Odor Detection Threshold (in water) = 11 ppb Coconut-peach like odor; in dilution, peach taste gamma-Undecalactone or 4-heptylbutanolide...C11H20O2 .......................... occurs in products such as Apple, Apricot, Butter, Cooked Pork, Cooked Rice, Passion Fruit, Peach. Mosciano, et. al. report that this material has a "creamy, fatty, fruity, coconut, peach, lactonic, fruity" odor and a "fatty, coconut, creamy, vanilla, nutty, peach" taste at 20 ppm. Discovered about 1900, this lactone has been the basis for Artificial Peach flavors for many years although it is only relatively recently (1965) that it was found in Peach as a very minor constituent. Odor Detection Threshold (in other) = 950 ppb Strong fatty, Peach-Apricot odor; Peach taste in dilution gamma-Dodecalactone or 4-octylbutanolide...C12H22O2 .......................... occurs in products such as Apricot, Beer, Blue Cheese, Cheddar Cheese, Cooked Pork, Milk Products, Peach, Pineapple, Rum, Strawberry. Odor Detection Threshold (in water) = 7 ppb Fatty, fruity, peach odor; milky-peach like taste   Data abstracted from Flavor-Base Copyright © John C. Leffingwell 1989-2010 Leffingwell & Associates In the news Home Copyright © Leffingwell & Associates TERMS OF SERVICE.............PRIVACY POLICY