Toward consistently good pinot noir

January 20, 2016
Toward consistently good pinot noir

The grapes used to make pinot noir, the red wine of hit comedy "Sideways" fame, are known to be literally and figuratively thin-skinned. They're highly sensitive to their environment, making it difficult for growers to determine their quality at harvest time. To get a better handle on the finicky fruit, scientists have now figured out how the grapes' aroma profile changes as they ripen. Their report appears in ACS' Journal of Agricultural and Food Chemistry.

As any wine connoisseur knows, aroma is a critical component to a vintage's quality. It changes as a matures, and ultimately, the blend of aroma-related compounds when the fruit is plucked from the vine determines how good the resulting wine is. But the current analytical techniques used to tell whether a grape is ready to be picked rely on sugar content and acidity. Michael C. Qian and Fang Yuan wanted to develop a way to determine maturity based on aroma.

The researchers identified 49 main odor compounds in young and ripe pinot noir grapes from two consecutive years, 2012 and 2013, using a technique called gas chromatography mass spectrometry. Of those, four were consistently found in mature grapes. Their results could help growers figure out the best time to harvest their crop and ensure its quality.

Explore further: Time is ripe for wine grapes

More information: Fang Yuan et al. Aroma Potential in Early- and Late-Maturity Pinot noir Grapes Evaluated by Aroma Extract Dilution Analysis, Journal of Agricultural and Food Chemistry (2016). DOI: 10.1021/acs.jafc.5b04774

Abstract
Aroma potentials in early and late maturity Pinot noir grapes were investigated in two consecutive vintages. The grape samples were hydrolyzed under acidic conditions, and the released odorants were studied by aroma extract dilution analysis (AEDA). Forty-nine main odor-active compounds were detected in the AEDA. The odorants released with high flavor dilution values were 1-hexanal, β-damascenone, guaiacol, and vanillin, together with C6-aldehydes and -alcohols, 4-vinylguaiacol, 4-vinylphenol, and 1-octen-3-one. The concentrations of aroma-active compounds were further quantitated. Compared with early harvest grapes, late harvest grapes released more β-damascenone, vanillin, 4-vinylguaiacol, and 4-vinylphenol in both years according to both AEDA and quantitation results, suggesting they were important aroma compounds that contribute to the characteristic of matured Pinot noir grapes.

Related Stories

Time is ripe for wine grapes

November 5, 2010

CSIRO researchers have discovered a new method growers could use to control when their grapes ripen, without affecting wine quality.

On the scent of a wine's bouquet

October 2, 2014

The majority of wines are produced from around 20 different types of grape, all of which have their own typical aroma. This is due to the terpenes, a diverse category of chemical substances including cholesterol and estrogen. ...

Botrytis 'noble rot' fungus reprograms wine grape metabolism

December 4, 2015

For hundreds of years, the fungus Botrytis cinerea has been key to making the world's finest dessert wines. Now UC Davis researchers working with Dolce Winery in the Napa Valley show how the fungus changes plant metabolism ...

Recommended for you

New method developed for producing some metals

August 25, 2016

The MIT researchers were trying to develop a new battery, but it didn't work out that way. Instead, thanks to an unexpected finding in their lab tests, what they discovered was a whole new way of producing the metal antimony—and ...

Force triggers gene expression by stretching chromatin

August 26, 2016

How genes in our DNA are expressed into traits within a cell is a complicated mystery with many players, the main suspects being chemical. However, a new study by University of Illinois researchers and collaborators in China ...

New electrical energy storage material shows its power

August 24, 2016

A powerful new material developed by Northwestern University chemist William Dichtel and his research team could one day speed up the charging process of electric cars and help increase their driving range.

Bio-inspired tire design: Where the rubber meets the road

August 24, 2016

The fascination with the ability of geckos to scamper up smooth walls and hang upside down from improbable surfaces has entranced scientists at least as far back as Aristotle, who noted the reptile's remarkable feats in his ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.