A. Chiralertpong, T.E. Acree, J. Barnard and K.J. Siebert
Espresso coffee samples were freshly prepared with 10% sucrose, 0.0143%
sucralose (equivalent in sweetness to 10% sucrose) or unsweetened, each
with and without non-dairy creamer. A sensory panel rated the
intensities of malty
, caramel
, roasty
, and coffee-like
. The
concentrations of flavor chemicals associated with the latter three
sensations (Furaneol, 2-ethyl-3,5-dimethyl (EDM) pyrazine, and
2-furfuryl thiol, respectively) were determined by gas chromatography,
using solid phase microextraction (SPME) sampling of coffee headspace.
Furaneol and furfuryl thiol were essentially unaffected by creamer
addition, but the more non-polar EDM pyrazine was greatly reduced. The
malty, caramel, roasty and coffee-like flavor intensities were not
significantly affected by creamer addition. This appears to be a case of
a disconnect between the absence of an odorant and perception. Furaneol,
furfuryl thiol and EDM pyrazine concentrations were unaffected by adding
either sweetener. The malty sensation was the same with and without
added sweetener. The roasty and coffee-like ratings both decreased to
similar extents in the samples with the two added sweeteners. The
ratings for caramel were considerably increased, again to a similar
extent, by both sweeteners. Since the added sweeteners were both
non-volatile, this is clearly a case where taste affected odor
perception.