Berry sugar and water loading

Principles and a few observations

Prof Alain Deloire [email protected]

Department of Viticulture and Oenology Stellenbosch University

UC-Davis, 10 May 2012 • Berry sugar and water loading: the concept

• Berry aromatic sequence and wine style: the concept

• Example of Merlot berry aromatic sequence

• Example of Cabernet Sauvignon berry aromatic sequence Berry quality = berry composition

- Each berry has its own dynamic of growth and ripening

- Each compound follows its own pathway

Hundred of compounds - Sugar - Minerals - Nitrogen - Amino acids - Water - Organic acids - Phenolic compounds - Aromatic precursors

-etc. A. Deloire 2011 Photons (µEinstein/m2/s)

Photosynthesis

Sucrose transportation via the phloem

Berry sugar loading (sucrose, glucose, fructose)

A. Deloire 2011 Berry sugar loading needs to plateau to achieve the ripening process (for red cultivars) berry volume evolution Brix accumulation of sugar per berry

sugar sugar sugar sugar

sugar

sugar

Beginning of veraison ripening harvest (berry softening) dates

A. Deloire, 2009 Berry water flux transpiration

berry phloem (water + sucrose)

xylem (water + minerals)

Sap conduction

pedicel

«water back flow » ?

Deloire, 2006, from Coombe, 1992; Rogiers et al., 2004. Berry sugar loading needs to plateau to achieve the ripening process

berry volume evolution Brix accumulation of sugar per berry

sugar sugar sugar sugar

sugar

sugar

1 2

Beginning of veraison ripening harvest (berry softening) dates

When sugar per berry plateaus, the volume of the berry could decrease by water loss and therefore the brix will increase A. Deloire , 2009 Which parameters are considered to establish the model of berry sugar loading?

- The Brix evolution over the ripening period, from veraison onwards

- The berry fresh mass evolution over the ripening period, from veraison onwards

- The sugar per berry (mg/berry) accumulation over the ripening period, from veraison onwards The key point of the ripening process

Sugar per berry accumulation

The profiles of sugar per berry accumulation we are looking for

Slow loading (water stress, unbalanced vine ?)

Beginning of veraison ripening harvest (berry softening)

Sugar loading: relevant indicator of vine functioning and balance Vivelys, Deloire 2008 Berry fresh mass (g) Sugar / berry (mg)

Brix Syrah Sugar / berry (mg) Sugar /

Brix

A. Deloire, 2012 Syrah Brix

Berry fresh mass (g) A. Deloire, 2012 Pinotage Sugar / berry (mg)

Brix A. Deloire, 2012 Shiraz

The plateau of anthocyanin biosynthesis is reached around 19 –20 brix.

Fournand et al., 2006. (Journal of Agricultural and Food Chemistry) ANTHOCYANINS’ EVOLUTION ACCORDING TO BERRY SUCROSE CONTENT Shiraz, Stellenbosch

600,00

500,00

400,00 anthL.T. anthGl. 300,00 Malv . mg/L anthCo. anthAc. 200,00

100,00

0,00 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 brix°

The arrow indicates the plateau for anthocyanins biosynthesis. Deloire et al., 2003; Fournand et al., 2007 The proposal is to:

- use Brix

- berry fresh mass

- and sugar accumulation per berry to predict the harvest date in relationship with the possible wine style.

HOW ? Matching wine style to harvest date for red cultivars in the Western‐Cape area using the berry sugar loading method Berry ripening versus style of wine

Berry Aromatic Sequence and Sugar Loading  Traditional indicators (brix, malic and tartaric acids, TAA, phenolics) are more related to the perception of the wine in the mouth.

 Therefore in association with the classical indicators of ripening, it is necessary to add new indicators which are more related to the style of wine in terms of aromatic profiles. Red cultivars: berry aromatic sequence (B.A.S.) Ripening levels and sugar loading

Fresh fruit, Fresh Neutral grassy skin Ripe Jammy fruit Pre ripe fruit fruit Pre fresh

Grassy

Berry tempo of ripening according to a physiological clock and to the style of wine

Vivelys, Deloire 2008 Merlot model

Berry tasting

22.8 – 25 brix 23.6 – 26 .7 brix

Vegetal green sugar / berry

fresh fruit ripe fruit aroma aroma

days Beginning of veraison 0152510 20

Day 0 = when sugar per berry reaches a plateau Vivelys, Deloire 2008 Merlot model

Berry tasting

22.8 – 25 brix 23.6 – 26 .7 brix

Vegetal green sugar / berry

ripe fruit aroma freshfresh fruit fruit ripe fruit aromaaroma aroma

days Beginning of veraison 0152510 20

Day 0 = when sugar per berry reaches a plateau Vivelys, Deloire 2008 Merlot Stellenbosch: classical canopy and treatment without lateral (warm climate) Biplot (axes F1 and F2: 88.57 %)

4

Trt_Mature_H4 3

AstringentT CookedVegA

2 Ctr_PreFresh_H1

Trt_Mature_H3

SoyaSavouryA 1 Trt_PreMature_H2 BlackcurrentA VegetativeFl

%) GreenplantlikeFl OverallBerryNose Ctr_Fresh_H3 BlackberryA 0

(14.60 BerrylikeFl

UnripeplumA

F2 GreenplantlikeA OverallBerryPalate BerryjamA

‐1

Trt_Fresh_H1

‐2

Ctr_Mature_H4

‐3 Ctr_Fresh_H2

‐4 ‐15 ‐10 ‐50 51015 F1 (73.97 %) Muller, Gobler et al., 2011 Merlot Durbanville (cool climate)

Biplot (axes F1 and F2: 79.51 %)

7 Fresh

5 BlackcurrentA

UnripeplumA SoyaSavouryA

OverallBerryPalate 3

Fresh

GreenplantlikeA %) BerrylikeFl 1 (25.45

F2 BlackberryA

Mature ‐1 OverallBerryNose

BerryjamA Mature Mature CookedVegA VegetativeFl ‐3

GreenplantlikeFl Fresh AstringentT

‐5 ‐15 ‐10 ‐50 51015 F1 (54.07 %) Muller, Deloire et al., 2011 Cabernet Sauvignon model

tannin reactivity

data data sugar loading pyrazine theoretical theoretical

fresh fruit mature fruit period period

day 0 day 20 day 25 day 45

Style of wine according to the sugar loading curve, which is a physiological « clock » (independent of calendar date)

Vivelys, Deloire 2008 How to be able to produce mature berry at low brix level?

How to manage:

- the volume of a berry

- the sugar per berry (loading and quantity)

- and therefore the Brix level

How to model berry sugar and water loading? Environment + vine functioning -T° - light = Berry composition -RH -pET Evapo‐transpiration - wind speed

exposed leaf area / yield H2O

Accumulation ‐ sugars ‐ water ‐ minerals (K+ Ca++ Mg+ etc.) ‐ nitrogen Fraction of Total Soil Biosynthesis Water transpirable by the vine (FTSW) ‐ phenol compounds, ‐ organic acids, Root development ‐ p‐aromas… Deloire, 2008 We acknowledge: - Winetech (funding) - Distell

- De Toren - Eikendal - De Grendel - Tokara - L’Ormarins - Solms Delta - Bottelary - Fairview VIVELYS - France « Share your knowledge. It is a way to achieve immortality » Dalai Lama, 2009 Thank you for your attention