(10-09-2017 08:50 AM)vinejo schreef:  Blind proeven is altijd een les in bescheidenheid, maar wijnen uit bepaalde landen kunnen soms heel herkenbaar zijn. Zo is cassis in Chileense wijnen soms heel dominant, en Australische wijnen vertonen veelal een opvallende eucalyptusgeur.
Ik vond op LpdV een studie die uitwijst dat die geur wel degelijk in de wijn kan verschijnen door de nabijheid van eucalyptusbomen.

Prepared 02 September 2005
Reproduced by permission
of ETS Laboratories
Monitoring Eucalyptus Flavor in Wine
New Capabilities at ETS
Examples of eucalyptol concentrations found in various California red wines

Analytical Details
Sample Size Required 125 mL
Fee Per Sample (1) $160
Fee per Sample (2-10) $135
Fee per Sample (11+) $130

“Eucalyptus” character is one of the most notable and controversial sensory expressions in some of California’s most prominent wines. Its presence is often related to eucalyptus trees growing near the vineyard area.

ETS has conducted research that has linked the “eucalyptus” aroma to the presence of eucalyptol (1,8-cineole) and has developed a method to detect and quantify its concentration in wine.

Analysis of eucalyptol is a powerful tool to measure the impact of eucalyptus growing in the vicinity of the vineyard, and to assist winemakers in objectively documenting their sensory impressions.

Significance of eucalyptol in wine
Eucalyptol (1,8-cineole) has a “fresh”, “cool”, “medicinal” and “camphoraceous” odor. It is the main component of the distinctive odor found in most eucalyptus species and represents 65 to 75% of the leaf oil from E.globulus, the predominant eucalyptus species in California.

In our research study, eucalyptol was detected in a variety of wines exhibiting a “eucalyptus” aroma. The flavor, perceived during tasting, appeared to be strongly related to quantified concentrations of eucalyptol as high as 20 µg/L. Aroma thresholds for eucalyptol were determined using a California Merlot. The difference and recognition thresholds were 1.1 µg/L and 3.2 µg/L respectively.

The study clearly demonstrated that eucalyptol plays a major role in the occurrence of “eucalyptus” character in wine.

Eucalyptus trees may introduce eucalyptol
to grapes by airborne transfer
The likely origin of eucalyptol in wine is via airborne transfer from eucalyptus tees to grape berries in the vineyards. Eucalyptol released into the atmosphere may be adsorbed by wax on the berry surfaces. It is subsequently dissolved during fermentation on the skins or extended macerations. This theory is supported by the observation that a “eucalyptus” character is rarely experienced in white wines.

A simple experiment confirmed the validity of this hypothesis. Cabernet Sauvignon berries were placed into a sealed jar containing one eucalyptus leaf for five days. The leaf was not in direct contact with the berries. Eucalyptol was detectable in the berries after this relatively short amount of time, while not detected in the control jars of cabernet berries without eucalyptus leaves.

Detection Methods
ETS has developed a method for quantifying eucalyptol in wine samples using an automated GC/MS system. The method allows detection below sensory thresholds with excellent precision.
Consequences and Applications
Monitoring eucalyptol content is a useful way to manage a significant flavor component in finished wines. Winemakers who wish to minimize or maintain consistent levels of “eucalyptus” character will benefit by determining eucalyptol concentrations in distinct wine lots.

Vineyard managers can use this tool to characterize vineyards close to eucalyptus groves and assess the impact of eucalyptus tree removal.

(10-09-2017 10:36 AM)wvd schreef:  

(10-09-2017 08:50 AM)vinejo schreef:  Blind proeven is altijd een les in bescheidenheid, maar wijnen uit bepaalde landen kunnen soms heel herkenbaar zijn. Zo is cassis in Chileense wijnen soms heel dominant, en Australische wijnen vertonen veelal een opvallende eucalyptusgeur.
Ik vond op LpdV een studie die uitwijst dat die geur wel degelijk in de wijn kan verschijnen door de nabijheid van eucalyptusbomen.

Prepared 02 September 2005
Reproduced by permission
of ETS Laboratories
Monitoring Eucalyptus Flavor in Wine
New Capabilities at ETS
Examples of eucalyptol concentrations found in various California red wines

Analytical Details
Sample Size Required 125 mL
Fee Per Sample (1) $160
Fee per Sample (2-10) $135
Fee per Sample (11+) $130

“Eucalyptus” character is one of the most notable and controversial sensory expressions in some of California’s most prominent wines. Its presence is often related to eucalyptus trees growing near the vineyard area.

ETS has conducted research that has linked the “eucalyptus” aroma to the presence of eucalyptol (1,8-cineole) and has developed a method to detect and quantify its concentration in wine.

Analysis of eucalyptol is a powerful tool to measure the impact of eucalyptus growing in the vicinity of the vineyard, and to assist winemakers in objectively documenting their sensory impressions.

Significance of eucalyptol in wine
Eucalyptol (1,8-cineole) has a “fresh”, “cool”, “medicinal” and “camphoraceous” odor. It is the main component of the distinctive odor found in most eucalyptus species and represents 65 to 75% of the leaf oil from E.globulus, the predominant eucalyptus species in California.

In our research study, eucalyptol was detected in a variety of wines exhibiting a “eucalyptus” aroma. The flavor, perceived during tasting, appeared to be strongly related to quantified concentrations of eucalyptol as high as 20 µg/L. Aroma thresholds for eucalyptol were determined using a California Merlot. The difference and recognition thresholds were 1.1 µg/L and 3.2 µg/L respectively.

The study clearly demonstrated that eucalyptol plays a major role in the occurrence of “eucalyptus” character in wine.

Eucalyptus trees may introduce eucalyptol
to grapes by airborne transfer
The likely origin of eucalyptol in wine is via airborne transfer from eucalyptus tees to grape berries in the vineyards. Eucalyptol released into the atmosphere may be adsorbed by wax on the berry surfaces. It is subsequently dissolved during fermentation on the skins or extended macerations. This theory is supported by the observation that a “eucalyptus” character is rarely experienced in white wines.

A simple experiment confirmed the validity of this hypothesis. Cabernet Sauvignon berries were placed into a sealed jar containing one eucalyptus leaf for five days. The leaf was not in direct contact with the berries. Eucalyptol was detectable in the berries after this relatively short amount of time, while not detected in the control jars of cabernet berries without eucalyptus leaves.

Detection Methods
ETS has developed a method for quantifying eucalyptol in wine samples using an automated GC/MS system. The method allows detection below sensory thresholds with excellent precision.
Consequences and Applications
Monitoring eucalyptol content is a useful way to manage a significant flavor component in finished wines. Winemakers who wish to minimize or maintain consistent levels of “eucalyptus” character will benefit by determining eucalyptol concentrations in distinct wine lots.

Vineyard managers can use this tool to characterize vineyards close to eucalyptus groves and assess the impact of eucalyptus tree removal.

Ik had dit al als waarheid aangenomen en dacht dat dit vele jaren geleden al vastgesteld was? Is het dan pas nu wetenschappelijk vastgesteld?

(10-09-2017 10:45 AM)vinejo schreef:  Neenee studie is van 2005 maar vond het interessant dit wetenschappelijk bewijs hier eens te posten. Telkens ik het verhaal van Kermit Lynch vertel van die Franse wijnbouwer die een wijn maakte met telkens dezelfde garriguetoets erin die echter plots verdwenen was na het verwijderen van de garriguestruiken naast de wijngaarden zie ik soms grote ogen trekken. (Wow, wat een zin, maar denk taalkundig nog net correct ;-) )

(10-09-2017 08:50 AM)vinejo schreef:  Blind proeven is altijd een les in bescheidenheid, maar wijnen uit bepaalde landen kunnen soms heel herkenbaar zijn. Zo is cassis in Chileense wijnen soms heel dominant, en Australische wijnen vertonen veelal een opvallende eucalyptusgeur.
Ik vond op LpdV een studie die uitwijst dat die geur wel degelijk in de wijn kan verschijnen door de nabijheid van eucalyptusbomen.

Prepared 02 September 2005
Reproduced by permission
of ETS Laboratories
Monitoring Eucalyptus Flavor in Wine
New Capabilities at ETS
Examples of eucalyptol concentrations found in various California red wines

Analytical Details
Sample Size Required 125 mL
Fee Per Sample (1) $160
Fee per Sample (2-10) $135
Fee per Sample (11+) $130

“Eucalyptus” character is one of the most notable and controversial sensory expressions in some of California’s most prominent wines. Its presence is often related to eucalyptus trees growing near the vineyard area.

ETS has conducted research that has linked the “eucalyptus” aroma to the presence of eucalyptol (1,8-cineole) and has developed a method to detect and quantify its concentration in wine.

Analysis of eucalyptol is a powerful tool to measure the impact of eucalyptus growing in the vicinity of the vineyard, and to assist winemakers in objectively documenting their sensory impressions.

Significance of eucalyptol in wine
Eucalyptol (1,8-cineole) has a “fresh”, “cool”, “medicinal” and “camphoraceous” odor. It is the main component of the distinctive odor found in most eucalyptus species and represents 65 to 75% of the leaf oil from E.globulus, the predominant eucalyptus species in California.

In our research study, eucalyptol was detected in a variety of wines exhibiting a “eucalyptus” aroma. The flavor, perceived during tasting, appeared to be strongly related to quantified concentrations of eucalyptol as high as 20 µg/L. Aroma thresholds for eucalyptol were determined using a California Merlot. The difference and recognition thresholds were 1.1 µg/L and 3.2 µg/L respectively.

The study clearly demonstrated that eucalyptol plays a major role in the occurrence of “eucalyptus” character in wine.

Eucalyptus trees may introduce eucalyptol
to grapes by airborne transfer
The likely origin of eucalyptol in wine is via airborne transfer from eucalyptus tees to grape berries in the vineyards. Eucalyptol released into the atmosphere may be adsorbed by wax on the berry surfaces. It is subsequently dissolved during fermentation on the skins or extended macerations. This theory is supported by the observation that a “eucalyptus” character is rarely experienced in white wines.

A simple experiment confirmed the validity of this hypothesis. Cabernet Sauvignon berries were placed into a sealed jar containing one eucalyptus leaf for five days. The leaf was not in direct contact with the berries. Eucalyptol was detectable in the berries after this relatively short amount of time, while not detected in the control jars of cabernet berries without eucalyptus leaves.

Detection Methods
ETS has developed a method for quantifying eucalyptol in wine samples using an automated GC/MS system. The method allows detection below sensory thresholds with excellent precision.
Consequences and Applications
Monitoring eucalyptol content is a useful way to manage a significant flavor component in finished wines. Winemakers who wish to minimize or maintain consistent levels of “eucalyptus” character will benefit by determining eucalyptol concentrations in distinct wine lots.

Vineyard managers can use this tool to characterize vineyards close to eucalyptus groves and assess the impact of eucalyptus tree removal.

(14-09-2017 08:59 PM)Jordaens schreef:  Dat artikel, of iets dergelijks, heb ik jaren geleden al eens gelezen op het forum van Wine Spectator. In die tijd waren daar nog Nieuw-Zeelanders en Australiërs aan het woord (en ook Finnen, Britten, Nederlanders en een enkele Belg...).

Probleem is natuurlijk dat eucalyptus ook heel nadrukkelijk de kop kan opsteken in b.v. Chileense wijnen. Zonder (voor zover ik weet) dat die struik in de buurt staat.

Wat die rook betreft: een aantal jaren geleden had ik een klant in Adelaïde, die een partij wijn wou liquideren, die hier in bond lag. Op dat moment stond een groot stuk van Zuid-Australië in lichterlaaie. Die mensen hebben toen zowat heel hun oogst kunnen weggooien, niet door de brand zelf, maar door de rook en het roet. Smoke taint indeed.