3 research outputs found
The Combined Effects of Storage Temperature and Packaging Type on the Sensory and Chemical Properties of Chardonnay
Californian Chardonnay was stored in five different wine-packaging
configurations at three different temperatures for a period of 3 months
to study the combined packaging and temperature effects on the sensory
and chemical properties of the wines. A trained descriptive panel
evaluated aroma, taste, mouthfeel, and color attributes, and the sensory
results were correlated to physical and chemical measurements including
volatile compounds, SO<sub>2</sub>, titratable and volatile acidity,
oxygen consumption, and wine color, using partial least squares regression.
In general, increased storage temperatures induced the largest changes
in the wines; however, significant packaging–temperature effects
were found for some attributes as well. Particularly wines stored
in bag-in-boxes at 40 °C showed significant increases in oxidized
and vinegar aromas and yellow color. Volatile esters also decreased
in these wines, while increased levels of compounds generally associated
with age- or heat-affected wine were found including 1,1,6-trimethyl-1,2-dihydronaphthalene
and furfuryl ether, consistent with previously reported chemical aging
reactions. In summary, storing unoaked Chardonnay in different packages
significantly changes the sensory and chemical properties depending
on the storage temperature. After a storage period of 3 months, bottle
storage with various closures (natural cork, synthetic cork, and screw
cap) changed the wine in a different way than bag-in-box storage
The Combined Effects of Storage Temperature and Packaging on the Sensory, Chemical, and Physical Properties of a Cabernet Sauvignon Wine
A Californian
Cabernet Sauvignon was stored for 6 months at three different constant
temperatures to study the combined effects of storage temperature
and packaging configuration. Glass bottles with natural cork, synthetic
cork, and screw cap closure, as well as two Bag-in-Box treatments,
were used in the experiment. A trained sensory panel was able to detect
significant changes in aroma, flavor, taste, mouthfeel, and color
attributes among the samples, differences that were found also with
various chemical and physical measurements (volatile profile, polyphenol
pattern, enological parameters, color space). Additionally, two commonly
used polyphenol assays were compared to each other in terms of their
ability to detect the changes in the polyphenol profile. Generally,
sample changes were more pronounced due to the different storage temperatures,
with 30 sensory attributes differing significantly among the three
different storage temperatures, while only 17 sensory attributes showed
a significant packaging effect. With increasing storage temperature
the packaging effect became more pronounced, resulting in the largest
changes in the Bag-in-Box samples stored at the highest temperature
of 40 °C. At the highest storage temperature, all wines showed
oxidized characters, independent of the wine packaging configurations,
but to a varying degree. Generally, wines that received highest oxygen
amounts and storage temperatures were much lighter, less red, and more
brown-yellow at the end of the 6-month storage period, compared to
their counterparts stored at 10 °C. These changes in color and
polyphenols, respectively, were also detected with the two spectrophotometric
assays. With increasing storage temperature both assays measured reduced
concentrations in total phenols and total anthocyanins, while total
tannins, degree of ionized anthocyanins, and color density increased.
Various volatile compounds differed significantly among the samples,
with largest relative concentration changes in acetates, organic acids,
and alcohols, in good agreement with previous literature reports,
with some being well correlated to specific sensory attributes too;
for example, various acetates correlated to cherry and fruit aromas
and flavors. The study shows that storage at elevated temperatures
could be a valuable tool for wine packaging screening and testing
new and improved wine packaging types under the worst conditions,
which are unfortunately not unrealistic
Understanding the Relationship between Red Wine Matrix, Tannin Activity, and Sensory Properties
One
major red wine mouthfeel characteristic, astringency, is derived
from grape-extracted tannins and is considered to be a result of interaction
with salivary proteins and the oral mucosa. To improve our understanding
of the role that the enthalpy of interaction of tannin with a hydrophobic
surface (tannin activity) has in astringency perception, a chromatographic
method was used to determine the tannin concentration and activity
of 34 Cabernet Sauvignon wines, as well as sensory analysis done on
13 of those wines. In addition, astringency-relevant matrix parameters
(pH, titratable acidity, ethanol, glucose, and fructose) were measured
across all wines. Tannin activity was not significantly correlated
with any matrix variables, and the perception of drying and grippy
was not correlated with tannin concentration and activity. However,
ethanol content was well related to mouthfeel attributes and appeared
to drive perceived drying. Although fructose and glucose content were
well correlated, they did not drive the perception of sweetness, which
is explained by the well-known mixture suppression effect