1. Technical Workshop | Tegniese Werkswinkel
15 November Kronenburg, R45, Paarl
PROGRAMME
08:00
REGISTRATION | REGISTRASIE
08:30
Shiraz SA Annual General Meeting Shiraz SA Algemene Jaarvergadering
09:00
Discussion & tasting: The effect of bleeding and use of stalks during fermentation on Shiraz Bespreking & proe: Die effek van sapbloei en gebruik van stingels tydens gisting op Shiraz
Riaan Möller
09:30
Tasting: Is German Shiraz the new kid on the block? Proe: Is Duitse Shiraz die nuweling om dop te hou?
Francois Haasbroek
TEA/COFFEE BREAK | TEE/KOFFIE-POUSE
10:50
An indepth discussion of the chemical and sensorial composition (including Rotundone) of 2016 Shiraz SA Wine Challenge Winners ‘n Omvattende bespreking oor die chemiese en sensoriese komposisie (ingesluit Rotundon) van 2016 Shiraz SA Wine Challenge wenners
Prof Wessel du Toit
11:15
A tasting and discusion of the 2016 Shiraz SA Wine Challenge winners Proe and bespreking van die 2016 Shiraz SA Wine Challenge wenners
Charles Hopkins
LIGHT LUNCH | LIGTE MIDDAGETE
12:50
How do French and South African winemakers describe Shiraz? Hoe beskryf Franse en Suid-Afrikaanse wynmakers Shiraz?
Dr Mihaela Minhea
13:15
International tasting: A comparative tasting and discusion focusing on the different styles of Shiraz available in the international market. International proe: 'n Vergelykende proe en bespreking gemik op die verskillende style van Shiraz wat in die internasionale mark beskikbaar is
Roland Peens

2. Viticultural information 2016 Top 12 Shiraz Challenge wines
Technical Workshop (15 Nov 2016)
page | 1

3. Winemaking information 2016 Top 12 Shiraz Challenge wines
Technical Workshop (15 Nov 2016)
page | 2

4. Wine sensory analysis 2016 Top 12 Shiraz Challenge wines
Windmeul
Eagles’ Nest
Alto
De Morgenzon
Rickety Bridge
Laborie
KWV The Mentors
Strandveld
Saronsberg
Cederberg
Fairview
Babylonstoren
Wine A
Wine C
Wine L
Wine O
Technical Workshop (15 Nov 2016)
page | 3

5. Polyphenol concentrations 2016 Top 12 Shiraz Challenge wines
Technical Workshop (15 Nov 2016)
page | 4

6. Rotundone concentrations 2016 Top 12 Shiraz Challenge wines
Rotundone ng/L*
Windmeul Shiraz Reserve
1.5
Eagles’ Nest Shiraz 2013 18
Alto Shiraz 2013 2
De Morgenzon Reserve Syrah 2014
4.5
Rickety Bridge Shiraz 2013
17.5
KWV Laborie Ltd Collection Shiraz 2014
1.3
KWV The Mentors Shiraz 2013
1.7
Strandveld Syrah 2012
13.5
Saronsberg Shiraz 2014
0.8
Cederberg Shiraz 2014
Fairview Eenzaamheid shiraz 2013
16.6
Babylonstoren Shiraz 2014
Wine A
2.4
Wine C
Wine L
3.7
Wine O
1.6
*Sensory threshold in wine: 16 ng/L
Highest value measured in Australian Shiraz: 122 ng/L
Technical Workshop (15 Nov 2016)
page | 5

7. Rotundone facts
Rotundone was first identified in 2008 by Australian researchers as the aroma compound present in Shiraz wines responsible for the peppery character.
It forms part of the terpene family and is classified as a sesquiterpene.
Rotundone is also the main aromatic compound found in white and black pepper.
It is also found in various other herbs and spices in nature such as thyme, oregano, rosemary and basil.
It has a sensory threshold of 16 ng/L in wine.
Rotundone has subsequently been identified in various other grape varieties above sensory threshold: Duras, Durif, Mouvèdre, Gamay noir, Schioppettino, Vespolina and Gruener Veltliner.
It can also be found in various other grape varieties such as Pinot noir, but usually in concentrations below the sensory threshold.
Concentrations of rotundone differ between different clones of the same cultivar.
The highest concentration reported for Shiraz is 620 ng/kg grapes. Highest concentration reported for Vespolina is 5440 (+/- 33) ng/kg grapes.
Rotundone concentrations in final wines are much lower than the initial concentration in the grapes.
Rotundone is very flavour active and very stable in wine over time.
It is a hydrophobic molecule and extraction is improved by the formation of alcohol during fermentation.
Rotundone is located in the grape skins (only), leaves, petioles and peduncles/rachises.
Leaves contain the highest concentration of rotundone followed by petioles, peduncle/rachises – whole bunch fermentation will increase rotundone levels in wine.
Rotundone is produced locally in the specific plant tissues and is not translocated via the phloem to berries.
Herbivore attack does not have a major effect like in the case of other terpenes.
Powdery mildew promotes higher rotundone levels in Duras grapes.
Rotundone is more abundant in cooler climates or years.
Temperatures above 25°C have a negative impact on rotundone concentrations in vines.
Rotundone concentrations are higher in shaded bunches than bunches exposed to direct sunlight.
Rotundone is derived from a pre-cursor α-guaiene and conversion starts at veraison and increases until approximately 44 days after veraison after which the concentration stays stable.
The most rapid rotundone accumulation is two weeks before harvest.
Increased water balance / irrigation from veraison to harvest increases rotundone levels in the vine.
Precision irrigation and canopy management strategies can increase rotundone concentrations.
People differ in their sensitivity for rotundone.
References are available on request.
Technical Workshop (15 Nov 2016)
page | 6