"Researchers have discovered an enzyme that plays a leading role in the formation of compounds that give aged wines their sought-after aroma.
The enzyme is a member of the cytochrome P450 family of enzymes, which are involved in the formation and breakdown of various molecules and chemicals. By analyzing a large sample of French grapes and white wines through a technique called liquid chromatograph mass spectrometry, the investigators found that, during grape growth, this enzyme (named CYP76F14) helps to convert a common plant compound, monoterpenol linalool, into a different compound, (E)-8-carboxylinalool. The formation of this compound is an important next step on the road to aroma: as wine ages, (E)-8-carboxylinalool is gradually converted into wine lactone, which gives old wine its nose.
In addition to contributing to our understanding of where wine aroma comes from, this discovery could also impact the grapevine breeding and wine making industries, other fruit research and breeding, as well as aspects of aroma and scent in the beverage and food industries.
Combining different analytical techniques was key in our work, and this broad picture helped us learn more about how common plant molecules are transformed into specific wine aroma," said Dr. Nicolas Navrot, senior author of the New Phytologist article."
Blake, thanks for sharing. I find the sentence “…is gradually converted into wine lactone, which gives old wine is nose” to be perhaps awkward or even a bit misleading.
Granted, I’m not a scientist, but I find it hard to group all “old wines” into a single bucket in terms of “nose”. I feel like each grape/region has such unique characteristics, especially when aged (to a point… I get that after long aging there’s some convergence).
Are they suggesting that wine lactone contributes to an aroma that virtually all “old wines” share?
Cytochrome P450, is also present in the human cells. And in great concentration in liver cells, catalyzing the breakdown of many medicals and toxins. Especially Paracetamoles, -and if the liver can’t break all paracetamol down completely, then the middle products (very toxic) will irreparable damage the liver.
Don’t eat a full glass of paracetamol, unless You are stuffed with Cyto P450.
Jason, I`m thinking that the convergence they are talking about still is an individual bottle thing and not just for one or all wines. The expression and influence of the enzyme surely must be something that evolves gradually over time until we can call it “aged” by whatever designation we want to give it. In this case, it would translate into when the enzyme has been fully expressed if in fact it reaches a point of completion. It would also seem to be reasonable to assume other factors such as temperature and humidity play a role in this process as well as cork integrity, use of SO2 and other chemicals, etc. Other thoughts?
You need Reidel to develop a glass for that enzyme.
Jason - why the skepticism? If all Pinot Noir or all Burgundy or all Bordeaux has the same aromas and flavors that are “delivered” by a particular glass, then certainly they’re smart enough to develop an “old wine” glass.
You’re really going to want some extra Glutathione S-transferase pi 1 (GSTP1) which is responsible for the breakdown of N-acetyl-p-benzoquinone imine (NAPQI), the toxic intermediate metabolite of acetaminophen (paracetamol for the Brits and elsewhere). An excess of CYP3A4 in particular could theoretically cause an increase in the formation of NAPQI and could lead to liver damage. Or you could just try not to eat more than a handful of Tylenol at a time and skip the whole metabolism conundrum altogether.
I could be wrong but this quote leads me to believe they only looked at Riesling and Gewurztraminer.
Wine samples
Wines were purchased from Paul Ginglinger (Eguisheim, France) or produced by the INRA Colmar (France). One sample (Riesling Weingut 2014) was purchased at the supermarket. The INRA Gewurztraminer wines were made from grapes collected from the same vineyard localized in the ‘Grand Cru Osterberg’ area in Ribeauvillé (France) in 1986, 1997, 1998, 2001, 2004, 2005, 2007 and 2009. All wines were stored in the INRA cellar, which is maintained at the constant temperature of 10°C. For the analysis of (E)-8-carboxylinalool and (E)-8-carboxylinalool glucose ester, wines were injected directly to LC-MS/MS without being extracted or concentrated. For the analysis of wine lactone, 40 ml of wine was spiked with internal standard ((E)-8-oxolinalool), then extracted with 10 ml pentane: ethyl acetate (1 : 1 v/v). The extract was then evaporated to dryness and the residue resuspended in 200 μl of methanol before LC-MS/MS analysis.