Oxidation Management of White Wines

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Oxidation Management

of

White Wines

A. C. Silva Ferreira*,A. Rodrigues, F. Bento, D. Geraldo, A. Silva, R. Martins, V. Lopes, C. Oliveira, P. Guedes Pinho

Universidade Católica Portuguesa, Porto, PORTUGAL

Objectives

Oxygen/Antioxidant :

- Mechanisms of consumption

“Resistance to Oxidation” :

- Shelf-Life Control

Random & Sporadic Oxidation :

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Melbourne 22-25, 2007 In Vino - Analytica Scientia 2007 3

Background : Key Odorants

A C. Silva Ferreira, Barbe J.C and Bertrand A.B. J. of Agric. Food Chem., 2003, 51 (5), 1373-1376. A C. Silva Ferreira, T. Hogg and P. Guedes de Pinho.

J. of Agric. Food Chem., 2003, 51 (5), 1373-1376. C H O C H 2 C H 2 S C H 3

White Wine

O OH O H3C H3C

Sotolon

Methional

Phenylacetaldehyde

CH O C H2

Porto, Sherry

Madeira Wines

O OH O H3C H3C

Sotolon

off - Flavor

in - Flavor

C H O C H ₂ C H ₂ S C H ₃

White Wine

O OH O H3C H3C

Sotolon

Methional

Phenylacetaldehyde

CH O C H2

Porto, Sherry

Madeira Wines

O OH O H3C H3C

Sotolon

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Melbourne 22-25, 2007 In Vino - Analytica Scientia 2007 5 O OH O H3C H3C

Sotolon

Methional

Phenylacetaldehyde

Rate of Formation Highly Dependent

Major flavor impact compounds …

CH O C H₂ C H O C H 2 C H 2 S C H 3

Background : Key Odorants

A C. Silva Ferreira, T. Hogg and P. Guedes de Pinho. J. of Agric. Food Chem., 2003, 51 (5), 1373-1376. A C. Silva Ferreira, Barbe J.C and Bertrand A.B. J. of Agric. Food Chem., 2003, 51 (5), 1373-1376.

Background:

Oxygen Chemistry …

O

₂

Ground State

Superoxide Anion

HO

₂

• O

₂

-HO

₂

-H

₂

O

₂

Perhydroxyl

Radical

Hydrogen Peroxide

Hydroperoxyl Anion

HO

• H

2 O

+

Hydroxyl Radical

O

₂

2-

Peroxide Anion

(pKa = 16-18)

(pKa = 11.6)

(pKa = 4.5-4.9)

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Background:

Oxygen Chemistry …

O

₂

Ground State

Superoxide Anion

HO

₂

• O

₂

-HO

₂

-H

₂

O

₂

Perhydroxyl

Radical

Hydrogen Peroxide

Hydroperoxyl Anion

HO

• H

2 O

+

Hydroxyl Radical

O

₂

2-

Peroxide Anion

(pKa = 16-18)

(pKa = 11.6)

(pKa = 4.5-4.9)

O

₂

2 H

₂

O

₂

HO

₂

Oxidized

Fe

2+

Fe

3+

H

2 O

₂

Fe

2+

Fe

3+

HO

Antioxidant

A

>

Antioxidant

B

Background: Oxidation Mechanism …

Coumaric acid Vanillic acid Resveretrol Malvidins Ferrulic acid Rutin Cafeic acid Gallic acid Epicatechin Quercetin Delphinidin Myricetin Ascorbic acid Catechin 800 750 650 470 300 210 360

Redox Potencial E (mV)

Kilmartin, P. A.; Zou, H.; Waterhouse, A. L. A cyclic

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Current

Intensity

I/ uA

Applied Potential Difference

E (vs ECS) / V

-5 0 5 10 15 20 25 0 0,2 0,4 0,6 0,8 1 1,2

E

Cyclic Voltammetry

Cyclic Voltammetry: Fundamentals

Coumaric acid Vanillic acid Resveretrol Malvidins Ferrulic acid Rutin Cafeic acid Gallic acid Epicatechin Quercetin Delphinidin Myricetin Ascorbic acid Catechin 800 750 650 470 300 210 360

Redox Potencial E (mV)

1st Inflection

Point

~ 0.6 V

2nd Inflection

Point

~ 1.0 V

3 mm diameter glass carbon electrode

Scan Range: 100 mV / sec (diffusion)

O2 2 H2O2 HO2 H2O2 O2

HO

Fe2+ Fe3+ Fe2+ Fe3+

Kilmartin, P. A.; Zou, H.; Waterhouse, A. L. A cyclic

voltammetry. J. Agric. Food Chem. 2000, 49, 1957-1965.

Treatment II

SO

₂

(free) = 50 mg/L

Treatment I

pH = 3.2

Treatment IV

pH = 4.2

Treatment III

O

2

dissolved = 8 mg/L

Stored @ T = 15 ºC ; @ T = 45 ºC

Sensory and Chemical analysis

•  Forced Aging Protocol

•  Normal Aged

Different Vintages (n=24) Age 1-20 years Old

_{- Group II -}

- Group I -

pH= 3.2 ; [SO2 ]free =12 mg/L ; [O2 ]= 1.0 mg/L

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Cyclic Voltammetry: Normal Aged Wines

QtCarv_9Yrs

Borba_2Yrs

Douro_4Yrs

Douro_6Yrs

FernP_7Yrs

Espor_4Yrs

Murça_2Yrs

-5

0

5

10

15

20

25

0.0

0.2

0.4

0.6 0..8

1.0

1.2 2Yrs

9Yrs

7Yrs

4Yrs

ΔI (µA)

E (vs ECS) / V

-5 0 5 10 15 20 25 0 0,2 0,4 0,6 0,8 1 1,2

a)

c)

c) white wine sample with 50 mg/ L of ascorbic acid

Ip1 ± s (µA) Ip2 ± s (µA)

13.7 ± 0.1

21.0 ± 0.2

15.3 ± 0.1

22.1 ± 0.1

17.3 ± 0.1

23.4 ± 0.3

a) white wine sample

b) white wine sample with 25 mg/ L of ascorbic acid

ΔI (µA)

O

OH

HO

Cyclic Voltammetry: Antioxidants Impact

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Cyclic Voltammetry: Antioxidants Impact

Ip1 ± s (µA) Ip2 ± s (µA)

13.7 ± 0.1

21.0 ± 0.2

16.0 ± 0.1

23.4 ± 0.2

a) white wine sample

b) white wine sample with 20 mg/ L of free sulphur

dioxide + 25 mg/ L of ascorbic acid.

O

OH

HO

SO

₂

-5 0 5 10 15 20 25 0 0,2 0,4 0,6 0,8 1 1,2

Supplemented_

b)

a)

&

ΔI (µA)

E (vs ECS) / V

0

6

12

18

24

0.2

0.4

0.6

0.8

1.0

1.2 Cyclic Voltammetry: Oxygen Impact

ΔI (µA)

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Data Treatment : Shelf Life Control Chart

0.4 0.6 0.8 1.0 1.2 E (vs ECS) / V 0 5 10 15 20 25 30 35 I / µA

Data Treatment : Shelf Life Control Chart

0.95 0.90 -150 -100 -50 0 50 100 -30 -20 -10 0 10 20 O2p0 Cp0 Cp4_15 Cp1_15 Cp3_15 0.6 V 1.0 V 0.4 0.6 0.8 1.0 1.2 E (vs ECS) / V 0 5 10 15 20 25 30 35 I / µA

R-SVD

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Melbourne 22-25, 2007 In Vino - Analytica Scientia 2007 17 O2p0 Cp0 Cp2_15 Cp3_15 Cp4_15 Cp5_15 O2p2_15 O2p3_15 pH4p2_15 pH4p3_15 pH4p4_15 SO2p1_15 SO2p2_15 SO2p3_15 SO2p4_15 SO2p5_15 pH4p0 P4 P1 P2 P3 P1 P2 P3 P4 P2 P3 P4 P1 P1 P2 _P3 P4

Data Treatment : Shelf Life Control Chart

O2p5_45 SO2p0 -150 -100 -50 0 50 100 0.6 V 1.0 V 0.95 0.90 pH4p4_45 Cp5_45 I / µA 0 5 10 15 20 25 30 35 0.4 0.6 0.8 1.0 1.2 E (vs ECS) / V B_3YAsc25mg/L B_3YAsc50mg/L B_3YSO220mg & Asc25mg/L

B_3YSO220mg SO2p5_45 -30 -20 -10 0 10 20

Data Treatment : SPE variable contribution

-150 -100 -50 0 50 100 -30 -20 -10 0 10 20 SO2p0 P3 pH4p0 SPE va ria bl e co nt rib ut io n 0.4 0.6 0.8 1.0 1.2 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

O

2

p0

SPE va ria bl e co nt rib ut io n 0.4 0.6 0.8 1.0 1.2 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

O

2

p5_45

SPE va ria bl e co nt rib ut io n 0.4 0.6 0.8 1.0 1.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2

SO

2

p0

SO2p5_45

P1 P2 _P3 P4 0.6 V 1.0 V P2 P3 P4 P1 O2p5_45 O2p0 Cp0 P1 0.95 0.90 pH4p4_45 Cp5_45 SO2p1_15 SO2p2_15 SO2p3_15 B_3YAsc25mg/L B_3YAsc50mg/L B_3YSO220mg & Asc25mg/L

B_3YSO220mg

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Melbourne 22-25, 2007 In Vino - Analytica Scientia 2007 19 -150 -100 -50 0 50 100 -30 -20 -10 0 10 20 SO2p0 P3 pH4p0 P1 P2 0.6 V 1.0 V P2 P3 P4 P1 O2p5_45 O2p0 Cp0 P1 0.95 0.90

Data Treatment : SPE variable contribution

O

2

p0

O

₂

p5_45

SO

₂

p0

SO2p5_45

RSD_4Y FP_7Y B_6Y Bb_2Y HE_4Y M_2Y E_10Y Q_9Y R_6Y SPE va ria bl e co nt rib ut io n 0.4 0.6 0.8 1.0 1.2 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

M_2Yrs

M_2Y Q_9Y SPE va ria bl e co nt rib ut io n 0.4 0.6 0.8 1.0 1.2 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

QCar_9Yrs

pH4p4_45 Cp5_45 SO2p1_15 SO2p2_15 SO2p3_15 B_3YAsc25mg/L B_3YAsc50mg/L B_3YSO220mg & Asc25mg/L

B_3YSO220mg

SO2p5_45 P3

PLS (MODEL) 1 Comps 2 Comps 3 Comps X (Methional) 68.2 79.88 86.99 Y (38 samples) 87.5 88.50 88.72 r (adjusted) 0.9121 0.9259

0.9248

C H O C H ₂ C H ₂ S C H ₃ CH O C H2 0 10 20 30 40 0 10 20 30 3 comps Pr ed ic te d [C ] µ g / L Measured [C] µg / L Measured [C] µg / L Pr ed ic te d [C ] µ g / L 0 2 4 6 8 10 0 2 4 6 8 10 3 comps

PLS (MODEL) 1 Comps 2 Comps 3 Comps X (Phenylacetaldehyde) 54.50 66.65 87.55 Y (45 samples) 79.32 82.18 82.83 r (adjusted) 0.8906 0.9065

0.9101

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A

C

A

B

D

E

F

G

F

D

A

D

C

_G

G

E

F

B

C

A

E

G

A

B

_E

Na

₂

SO

₃

~ SO

₂

free > 200 mg/L

Tartaric Acid ~ pH = 2.5

Oxygen Permeability : Experimental Design

2 SO

₃

2-

_{+ O}

2 2 SO

4 -2

Horizontal Storage 10.0 20.0 30.0 40.0 50.0 0 150 300 450 600 750 900

time (days)

[O 2] m g /L Vertical Storage 10.0 20.0 30.0 40.0 50.0 0 150 300 450 600 750 900

time (days)

[O 2] m g /L

[O

2

] = 0.03 mg/L/day

x

t (days)

Nat-1st_trA

Nat-2nd_trA

Nat-2nd_trB

“Agl"-1st_trA

" Agl

"-1st_trB " Agl

"-2nd_trA

Oxygen Permeability

: Storage Position

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Melbourne 22-25, 2007 In Vino - Analytica Scientia 2007 23 200.00 150.00 100.00 50.00 0.00 50.00 100.00 150.00 200.00