The AWRI is a member of the Wine Innovation Cluster

Volatile aroma compounds related to ‘stone fruit’

aroma in Viognier and Chardonnay wines

Tracey E. Siebert1,2, Wes P. Pearson1, Alice Barker1, Sheridan R. Barter1,

Miguel A. De Barros Lopes2, Philippe Darriet3, Markus J. Herderich1 and I. Leigh Francis1,2

1 The Australian Wine Research Institute, PO Box 197, Glen Osmond (Adelaide) SA 5064, Australia2 University of South Australia, School of Pharmacy and Medical Science, City East Campus, Adelaide, SA 5000, Australia

3 University of Bordeaux, Unité de Recherche Œnologie EA 4577, ISVV, Villenave d'Ornon cedex, 33882, France

Corresponding author’s email: tracey.siebert@awri.com.au

Background

The compounds that give rise to the important ‘stone fruit’ aroma characters in white wine are not well understood. Relating the compositional differences among wines to their sensory

attributes can help determine if sensory difference is due to variation in concentrations of aroma compounds, an absence/presence of certain aroma compounds or an additive effect of several

aroma compounds. This study focused on Viognier and Chardonnay wines from France and Australia with differing levels of ‘stone fruit’ character, ranging from low to high.

Sensory analysis

A set of 18 commercial wines (six wines each of: Australian Chardonnay, Australian Viognier and French Viognier) were selected for descriptive sensory analysis.

Radar plot of the mean aroma sensory data of four different winesReference standards used to define the aroma attributes A sensory panel training session

Important volatile compounds to explain ‘apricot’ and ‘peach’ aroma attributes.

Of the 109 targeted wine aroma compounds, 79 were detectable and quantified in the 18 wines.

γ-Nonalactone, γ-decalactone and the previously little studied and potent ‘dairy lactone’ were

associated with the ‘apricot’ sensory attribute, together with the monoterpenes linalool, geraniol

and nerol, and the compounds E-2-hexenal and E-2-hexenol. The polyfunctional thiol 3-

mercaptohexyl acetate (3MHA) and ethyl cinnamate were negatively related to the apricot attribute.

The ‘peach’ aroma attribute was also associated with the ester 2-methylpropyl acetate.

Conclusions

The n-alkyl γ-lactones are impact aroma compounds in actual stone fruit and γ-nonalactone and γ-decalactone plus dairy lactone were associated with apricot aroma in the wines studied,

together with several monoterpenes and aldehydes. While the lactones were present below reported aroma threshold values, it may be that a combination of compounds gives rise to the ‘stone

fruit’ flavour. Further work will include reconstitution, addition and omission studies to confirm the importance of these compounds to ‘stone fruit’ aroma in wine.

Aroma

attributeStandard added to wine

Passionfruit passion fruit pulp, tinned

Pineapple pineapple pieces, fresh; pineapple juice, tinned

Apricot apricot pieces, tinned

Peach white peach pieces, fresh, no skin

Lemon lemon slice with rind, fresh

Lime lime slice with rind, fresh

Floral linalool solution; 2-phenylethanol solution

Grassy grass, fresh; green bean, chopped; no wine

Vegetal asparagus juice, tinned

Box hedge box hedge leaves; no wine

Honey honey

Butter butter

Nutty mixed nuts; no wine

Flint benzenemethanethiol solution

Sweaty/cheesy hexanoic acid + 3-methylbutanoic acid solutions

Pungent ethanol

Kerosene 1,1,6-trimethyl-1,2-dihydronaphthalene solution

Chemical and statistical analysis

Volatile compounds were measured in the wines using previously published and in-house methods. The wines were also analysed for standard chemical parameters. The sensory attribute ratings

were related to volatile composition by partial least squares regression. (PLSR).

The descriptive sensory analysis data showed the 18 selected wines

had widely differing ratings of ‘apricot’ and ‘peach’ aroma attributes

and the two attributes were not closely correlated.

PLSR of chemical composition and sensory aroma attributes

X-variables are volatile compounds plus standard chemistry and Y-variables are aroma attributes.

-0.04

-0.03

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-0.01

0.00

0.01

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0.04

0.05

Et

Pr

Ac

Aci

d

2-P

hEt

OA

c

Ge

ran

iol

Lin

alo

ol

Ne

rol

Gu

aia

col

tr-O

ak

lact

on

e

Va

nil

lin

Eth

yl c

inn

am

ate

3-M

HA

γ-N

on

ala

cto

ne

γ-D

eca

lact

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Da

iry

lact

on

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E-2

-He

xen

al

Be

nzA

ld

No

ne

nal

E-2

-He

xen

ol

Apricot

-0.04

-0.03

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-0.01

0.00

0.01

0.02

0.03

0.04

0.05

Et

2-M

eP

r

2-M

eP

rOA

c

Et

2-M

eB

u

Et

3-M

eB

u

3-M

eB

uO

Ac

Et

De

c

Ge

ran

iol

Lin

alo

ol

Ne

rol

Me

SH

Be

nzA

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Peach

γ-Nona γ-Deca Dairy

Minimum ̶ maximum (n=18) 2.0 - 6.1 0.4 - 1.3 0.01 - 0.06

Aroma threshold in MW* 76 10 0.1

*Model Wine, published data

Significant aroma

compounds

Lactones (µg/L)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

Overall Fruit

Passionfruit

Pineapple

Apricot

Peach

Lemon

Lime

Floral

GrassyVegetal

Box Hedge

Honey

Butter

Flint

Sweaty/Cheesy

Kerosene

Pungent

VIOGNIER 2012

VIOGNIER 2011

VIOGNIER 2009

CHARDONNAY 2012

Acknowledgements

Panagiotis Stamatopoulos, Pascaline Redon, ISVV.

Sensory panellists, AWRI.

-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1

-1

-0.9

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-0.1

0

0.1

0.2

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0.6

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0.8

0.9

1

EtOH

Flavonoids

G+F

OD

pH

SG

FSO2

TSO2

TA pH 8_2

Cinnamates

Phenolics

VA

EtOAc

Et Pr

Et 2-MePr

2-MePrOAc

Et Bu

Et 2-MeBu

Et 3-MeBu

2-MePrOH

2-MeBuOAc3-MeBuOAc

BuOH

2-MeBuOH

3-MeBuOH

Et HexHexOAc

HexOH

Et Oct

Ac Acid

Pr Acid

2-MePr Acid

Et Dec

2-PhEtOAc

Et Dodec

Hex Acid

2-PhEtOH

Oct Acid

Dec Acid

Acetoin

2,3-BuDiol

α-Terpinβ-Damasc

Geraniol

LinaloolNerol

Rose oxide

TDN

CS2

DMS

H2S

MeSH

4-EG4-EP

4-Me-G

5-Me-furf

cis-Oak

Furfural

Guaiacol

tr-Oak

Vanillin

Et 9-decen

b-Citron

Et cinn 4-MMP

3-MH

3-MHA

FFT

BM

γ-Octa

γ-Nona

γ-Deca

6-Amyl-α-P

γ -Dodeca

Methionol Homofuran

Maltol

2-MePrAld

Sotolon

2&3-MeBuAld

Eugenol

Hexanal

E-2-hexenal

Methional

BenzAld

Ph-AAld

Nonenal

Mesityl Ox

Z-3-Hexenol

E-2-Hexenol

Overall Fr

Passionfruit

Pineapple

Apricot

Peach

Lemon

LimeFloral

Grassy

Vegetal

Box Hedge

HoneyButter

Nutty

Flint

Sweaty/ Cheesy

Kerosene

Pungent

Dairy