Arnica Rowan examines ways of producing lighter wines when global warming suggests otherwise.
Across the planet, consumer preferences are swinging to less concentrated, lower-alcohol beverages. Meanwhile, the global wine industry is facing increasing temperatures, resulting in grapes with higher sugar content at phenolic ripeness, and producing super-concentrated, higher-alcohol wines. Australian red wine’s average alcohol has risen by 2% since the 1980s, to 14.4% today (see this report). Global warming is the Achilles heel of the wine industry.
While wine industry advocates are wringing their hands, wondering in North America how they are going to compete with the runaway success of the White Claw hard seltzer, grape farmers have started doing what farmers do best – innovating. On the undulating flatlands of Marlborough and the fringes of the Gobi desert, vines are being tended differently. The farmer’s methods are simple but effective, naturally lowering the alcohol of the wines.
Across the Tasman Sea from the blistering land down under, a Kiwi farmer has made it his life’s work to produce high-quality wine with substantively less ethanol. Seventeen years ago, Dr John Forrest started to experiment with leaf removal, slowing the sugar development in the vine’s grapes. When he presented his first lower-alcohol wine, The Doctors’ Riesling at 8.5% alcohol, he couldn’t believe how popular it was among educated professional women. With rapid retail rebuys, it was a cult success.
Dr Forrest began to use the same plucking techniques in his Sauvignon Blanc vineyards, and other New Zealand producers started taking note. He told me over the phone from his home in Marlborough that the greatest danger to his wines’ success was for other Kiwi wineries to adopt mechanical methods to create their own lower-alcohol, but lower-quality wines. The solution was to share his knowledge freely, and to enable other local farmers to lower alcohol naturally: ‘It was better to share and raise the standard for everyone. After all, a great idea is only a great idea if everyone is able to execute it.’
So in 2014 Forrest (below) teamed up with 15 other New Zealand wineries to launch the largest research project ever conducted in the New Zealand wine industry. The goal of the $17-million programme, funded by New Zealand Winegrowers and the Ministry for Primary Industries, was to create a new, lower-alcohol category of wine leveraging Forrest’s canopy-management methods. The project focused on innovative vineyard practices that could be scaled up industrywide.
During our call, Forrest laughed wryly: ‘I didn’t want to die being known as being the doctor of low alcohol, but now I’ve given up and accepted it. Lighter alcohol has been so successful all over the world, it’s been a unique privilege to be at the start of the phenomenon.’
So far, 27 wines have resulted from this co-ordinated effort, all under 10% alcohol. The difference between these and 5% low-alcohol wines typically seen on the supermarket shelves is in the production methods – the five percenters generally have their alcohol physically removed or diluted – and, importantly, the sensory profile. In other words: New Zealand’s lighter wines taste like real wine.
According to Forrest, the secret is to address the sensory experience of the wine with thoughtful winemaking. For example, he ferments 5% of his Sauvignon Blanc in barrel, just to deepen the colour and texture of the wine to what New Zealand wine fans are accustomed to.
The impetus behind the Forrest lower-alcohol project was to create a new wine category for thirsty consumers. However, his techniques are potential solutions to the rest of the world’s warming climate and rising wine alcohol levels.
Dr Nicholas Cradock-Henry, researcher at Manaaki Whenua Landcare Research in Lincoln, New Zealand, explained to me via Zoom that many global wine regions will face more extreme temperature challenges than his island home.
‘Making predictions is difficult', he admitted, ‘however, modelling results suggest that globally, the current area suitable for viticulture will decrease between 25% and 73% by 2050. That’s a high-emissions scenario. But even if we calculate with mid-range emissions, we’ll lose 19% to 62% of our viticultural area, if we are using today’s practices. Soon, more moderate wine climates will be warm, and warmer climates will face extreme temperature pressure.’ He did point out, however, that higher temperatures may also continue to open up new areas for wine grape-growing, as we have seen in northern Europe.
In the Ningxia wine region in northern China, the winemakers of Chateau Changyu Moser XV are already creating wine in conditions their global counterparts are dreading. The land is dry, the sunshine is relentless; the winters so cold that farmers have to bury the vines to protect them from fatally low temperatures. Only 100–150 mm (4–6 in) of rain fall in the whole year, usually in two or three massive storms. The winery grows little other than Cabernet Sauvignon, but makes red, rosé and, unconventionally, white wines from the variety.
Chateau Changyu Moser XV‘s pioneering Austrian partner Lenz Moser, seen at the top of this article sorting Cabernet grapes, is constantly refining viticultural methods to find balance in the Chinese climate. As we sat together at the Vancouver Wine Festival, he explained to me how tiny the Cabernet berries are – pointing at his smallest fingernail. Moser’s battle for balance is a fight against concentration, and his lessons are valuable for other winemakers’ impending challenges. 'If I have to use unusual methods to get harmonious, complex wines, I will do it', he explained to me with enthusiasm.
Moser’s main techniques include water management and yeast selection, and he is trialling methods to bring forward harvest dates. The Ningxia vineyards are fed by periodic flooding, channeling water from the Yellow River between the vines. The watering cycle is quick – approximately every six weeks water soaks the roots of the vines and then immediately drains deep into the loose, sandy-loam soil. The vineyard staff time the flooding for just before the start of harvest; if the time interval between the last flood and the harvest is too great, the wines will be too concentrated.
Once the Cabernet Sauvignon grapes reach the winery, Moser is employing unusually inefficient, or, as he calls them, ‘lazy’ yeasts to ferment the wines. The white Cabernet Sauvignon is made with Champagne yeast which produces less alcohol. He is also experimenting with old, heritage yeast strains from various parts of Europe, finding suitably lethargic matches for the red and rosé wines.
Moser’s next round of experiments is designed to advance the grape harvest date. His hypothesis is that if he can filter the unripe green-brown seeds out of the grape must before fermentation, he’ll avoid the unripe tannins that can blight wine from early-picked grapes. His initial 2019 experiments using less-ripe grapes produced, according to him, the best Cabernet Sauvignon (red) from Chateau Changyu Moser XV to date.
The ongoing experiments are a necessity, according to Moser. ‘We really have to get our heads around this, controlling the concentration and alcohol. It’s getting warmer, and I want to keep making Cabernet Sauvignon.’
Dr Cradock-Henry of New Zealand warned me that in the future not all wine producers would be able to produce good wine from the grapes they are accustomed to. ‘For perennial crops such as wine grapes, the effect of climate change on phenology may require a change', he said. ‘Farmers will have to consider grape varieties adapted to warmer climates.’
The spiritual home of Cabernet Sauvignon, Bordeaux, shocked the wine world this past June when the AOC Bordeaux producers' association announced that they would be trialling seven new grape varieties. Experimentation with red wine varieties such as Arinarnoa, Castets, Marselan and Touriga Nacional and pale-skinned varieties Alvarinho, Liliorila and Petit Manseng is intended to empower vignerons to adapt to the region’s rapidly changing climate. For example, Arinarnoa is a Cabernet Sauvignon x Tannat cross that offers excellent disease resistance, the quality characteristics of its parents and, best of all, naturally low sugar levels.
For now, the new grape varieties may represent only 10% of an AOC Bordeaux blend but the policy will be reassessed after 10 years of experience. The policy was driven by the Bordeaux Wine Council (BIVB), which invested over €2 million in climate-change research, mainly supporting test plots for 52 varieties and 55 different rootstocks. It’s not a lot of money compared with New Zealand’s low-alcohol research investment, but the results should complement the work of their counterparts from the southern hemisphere.
To quote the business leader and philanthropist Bill Gates, ‘innovation requires the ability to collaborate and share ideas with other people, and to sit down and talk with customers and get their feedback and understand their needs.’
Consumers are speaking clearly with their purchases. They want lower-alcohol wines that don’t compromise on flavour. Now thanks to innovators such as Forrest and Moser, the global wine community has natural techniques to meet the wine lover’s needs while adapting to climate realities across the globe. Cheers to that.