New dawn for Sulphur Free Wines?

Tuesday, 11 December, 2018
Dave March CWM
In 2010 Audacia owner Trevor Strydom was given a cup of Rooibos tea by his daughter as he pondered how he could differentiate his wine. He was looking at the answer.

It started by adding Rooibos wood chips to wine and a unique range of red wines was born. Audacia is now well established and known for their Rooibos Wooded ‘No Sulphur Added’ wines worldwide. They have a strong global following and in China the wines are even sold in pharmacies and promoted for their health qualities.

Trevor sought to patent the use of Rooibos in wine when his scientist patent lawyer suggested looking at both Rooibos and Honeybush plants for their broader antioxidant and antimicrobial properties. A partnership between Audacia, KWV and Namibia Breweries ‘Red Dawn IP Holdings’ was born and research and testing ensued. The first step was to move away from wood chips and develop a soluble powdered extract or tannin.

Further trials showed that Honeybush tannins were far more effective as a preservative in wine.

“The journey has had its challenges. When South Africans hear Rooibos or Honeybush, they automatically think of “tea”, says Project Lead Rina McKellar. “No one wants to associate wine with tea, especially not winemakers! We knew we wanted to capture the plant qualities, but without the taste or the connection to tea”.

The answer was found in the dosage of Honeybush tannin extract. The amount required to effectively preserve wine is so low that no colour or flavour impartation is observed.

Publicity material says it ‘optimises both the antimicrobial and polyphenolic content without imparting bitterness or affecting the character of traditional wine cultivars’.

Tests soon also revealed a wide range of qualities, some of which surprised the team.

Adding ‘RDNT Genesis’ – the product produced by Red Dawn  – in very small amounts, around 2 grams for white wine per 100 litres, meant that because of its antioxidative properties no sulphites need to be added during the wine making process.

RDNT Genesis’ tannin can be added to grape bins or at the crusher, before fermentation or before bottling and is so effective that Rina showed me technical sheets for some wines which had free sulphur often at zero and total sulphur usually under 5 parts per million (ppm) total. “Consumers are wanting healthier option wines, so ‘Sulphur Free’ wines will become more prevalent”, says Rina, and KWV’s ‘Earth’s Essence’ range (which uses Genesis) is already successful in the UK, Finland, and the Netherlands. The ‘Earth’s Essence’ Shiraz has zero sulphur, not just none added, but none in total having had 5.5g/hl of Genesis added during winemaking. Tim Atkin MW scored the wine (Earth’s Essence Chenin Blanc) at 89 points. 

Less than 10 ppm sulphur means that a wine can be labelled ‘No Added Sulphur’ in SA, and bottles won’t need to state ‘Contains Sulphites’, either. “No-one would bottle a Chenin Blanc at zero free and less than 10ppm total sulphur”, says Rina. The legal limit for sulphur in white wines in SA is 200ppm (150ppmin reds) so around 5ppm is insignificant.

Thys Loubser, winemaker at Robertson Winery agrees that the future will see more “No Sulphur Added” wines, adding that consumers need not be afraid to demand more choice from their retailers.

Also trialling RDNT Genesis, Fairview winemaker Annette van Zyl wanted to produce a wine without the use of SO2 during or after the winemaking process. Not knowing what to expect, we were pleasantly surprised at the fruity aromas and freshness the wines retained”. Annette adds, ‘it is also effective at very low dosages and contributes to a perception of sweetness without changing the RS or adding a tea- like character’.

Innovation Manager Arnold Vlok tells how opened bottles of wines remain resistant to oxidation using the tannin, “We tasted one bottle recently opened eight days earlier and it still showed no signs of oxidation”. An accelerated shelf life test to stimulate four years of aging on wine showed better resistance to oxidation and preservation of organoleptic qualities than wine under SO2.

During the last few years of trials (and Arnold stresses how much more there is to learn about Honeybush tannins) other effects have emerged.

Trials indicate that Genesis Tannin may promote initial fermentation and keeps the ferment healthy. It improved body and mouthfeel and having tasted barrel samples of 2018 Cabernet Sauvignon, Merlot, Shiraz and Cabernet Franc it is evident to me that wines retain their structure and tannins, but become softer when young. Also evident was freshness and very clean flavours, intense fruit profiles and very deep colour. Arnold believes Genesis also makes fruit components seem sweeter and can improve fining.

With only 400 tonnes of Honeybush available annually, the Western Cape Government has welcomed the initiative and has approved the tannin additive for use in wine production. Future farming opportunities of a truly indigenous plant got the thumbs up from Alan Winde who has welcomed the innovation warmly (link to clip below).

The Red Dawn team are very excited about the future and what ongoing trials may reveal and they stress they may only be at the beginning, but already several wineries have shown interest. Assistant winemaker at Neethlingshof, Jacobus Van Zyl is very happy with results so far. He used Genesis on two 400L tanks of Sauvignon Blanc and found that compared to a control tank the wine was fresher and though the ferment of the control tank was difficult the trial tanks went through fermentation smoothly. Jacobus didn’t use the product for reducing SO2, but was looking to protect juice phenolics, especially preserving aromatics in white wines and the success of his trials means he is “really looking into continuing with it”.

Rina knows some winemakers may not be ready to make the leap to “no sulphur added” wines just yet, so invites them to trial it alongside their traditional methodology until they feel confident enough to reduce their sulphur levels, “ultimately this is the beginning of a journey” she says.

There are other providers of methods to produce sulphur free wines and whilst I suggested that Genesis tannin may be too good to be true, Rina assured me that this was a wholly natural, indigenous plant full of health properties with which they are seeing phenomenal results, it imparts no foreign flavour and improves many facets of a wine.  In a world looking for healthier alternatives – whether or not there is a link between sulphur and headaches – this could be an exciting journey.

Alan Winde clip:

Red Dawn
Red Dawn

Earth's Essence
Earth's Essence

more news