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Odor
Properties & Molecular
Visualization
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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
.............................![](c5_glac.gif)
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
..............................![](c6_glac.gif)
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
..........................![](c7_glac.gif)
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
..........................![](c9_glac.gif)
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
..........................![](c10_glac.gif)
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
..........................![](c11_glac.gif)
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
..........................![](c12_glac.gif)
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
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© John C. Leffingwell
1989-2010
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