Read this in Wine Business Monthly (You only need to register to have archive access)
Issue:April 2015
The article has various charts (referenced in this copied portion but not included) including "Oak Aromas", "Characteristics Flavor", etc. Also (not included here) the article provides information from trials on "oak impact on neutral barrels"
I was curious about "microoxygenation" and wondering if anyone has used a form of it after fermentation, and also found the statements in this article in regard to accelerated aging interesting and perhaps applicable to this thread.
Any issue with my copy/paste or otherwise...my apologies
Benefits of Oak Add-ins
The main reason for using forms of oak other than barrels is obviously cost,
but doing so can also speed up aging and ensure consistency. According to
Chauffour, while barrels can take years to impart the desired effect, while
mini-staves take only months, and the tannin impact is nearly instant.
In terms of cost, new barrels run $200 to $400 per hectoliter (26.4 gallons),
neutral barrels cost $40 to $100, and alternatives can cost $0.30 to $12 per
hectoliter. These alternatives can be used to boost the oak properties of
neutral barrels or as an alternative way to provide oak aromas in stainless
steel tanks; though you would need to use microoxygenation to better replicate
the effect of barrels.
Chauffour pointed out that the extractable component of oak consists of
only 5 to 10 percent of its composition. Other inert components are lignin
(25 to 30 percent), cellulose (40 to 45 percent) and hemicellulose (20 to 25
percent). The extractable portion contains aromatic compounds, ellagitannins,
other polyphenols, such as lyoniresinol, that contribute bitterness and
quercotriterpenosides that add sweetness.
However, the impact of the oak on wine depends on many characteristics,
including the origin, forest and species of oak, the age of the wood and how
it’s processed (such as whether it’s sawn or split), how long the pieces are
aged and how, and the type and degree of toasting.
As an example, French and American oak species differ significantly in
extractable compounds, notably the so-called Whiskey lactones that give
American oak (and Bourbon) its characteristic flavor (TABLE 1 ).
Different components in wood also deteriorate at different rates. Ellagitannins,
for example, drop linearly from 55 μg/g in 30-year-old wood to about 3
in 180-year-old wood. However, b-methyl-g-octactone actually rises from 30
to 45 years then deteriorates by half at 120 years (Moutonnet, 2012).
Different compounds contribute the flavors and aromas we associate with
wine aged in wood (TABLE 2 ).
While barrel alternatives can’t contribute to the same slow addition of
oxygen that barrels can, microoxygenation will, and in a more controlled
manner. In addition, oxygen is added when the alternatives are added.
One of the most interesting aspects of using oak alternatives instead
of traditional new oak barrels is that the winemaker can choose different
flavor additions, the same way a chef can add spices. These flavors are
determined by the drying time and length and temperature of toasting the
oak chips or staves.
Enartis Vinquiry, for example, selects its oak alternative range by aromatic
profile to offer a range of consistent flavors (FIGURE 1 ).
