restektn07 - page 143

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20
Figure 23
The γ-lactones are analyzed for the adulteration of
peach flavor on the Rt- βDEXsa column.
19 0min. 38
γ-decalactone
γ-dodecalactone
R
R
S+
30m, 0.32mm ID, 0.25µmRt-βDEXsa (cat.# 13108); Oven temp.: 60°C (hold 2min.)
to 100°C@ 15°C/min., then to 220°C@ 3°C/min.;
Carrier gas: helium; 60cm/sec. set @ 60°C; Detector: MSD set @ 220°C.
γ-undecalactone
R
γ-undecalactone
R S
Rγ-decalactone
γ-octalactone
R S
PeachFlavor
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Both δ- and γ-lactones are present in
peaches, but only the γ-lactones are
analyzed for theadulterationofpeach
flavor.Gamma-decalactoneoccurs in
the 89% (R) : 11%(S)- enantiomers in
natural Peach flavor.8 In Figure 23,
Chromatogram A is a peach extract.
A significant amount of the (R)-γ-
decalactone was present, along with
the (S)-enantiomer, which coeluted
withanunknown. A small amount of
(R)- γ-dodecalactone was also de-
tected.ChromatogramB isanextract
from a beverage with “all natural”
peach flavor. Gamma-decalactone
was not present, but racemic γ-
undecalactonewas found ina1:1 ra-
tio. Thiswas thesame resultwithan-
other peach-flavored beverage.
ChromatogramC is froman “allnatu-
ral-flavored beverage,” with peach
andvanilla flavors. Althoughonly the
(R)-enantiomer of γ-decalactone was
present, the amount is very small.
Both γ-octalactone and γ-undecalac-
tone were found to be racemic, indi-
cating adulteration.
A: Peach Extract
B: Peach Flavor
C: Peach/Vanilla Flavor
The γ-lactones are
inspected for the
adulteration of
peach flavor.
S