Whatever happened to big, boozy wine?

It is widely believed that, thanks to ever-warmer summers, wine is becoming steadily more potent, but this is far from the whole picture — and the picture is continuing to evolve in some unexpected ways.

Some older wine drinkers might remember seeing 10.5 per cent on the label of some Bordeaux wines back in the 1970s. At the time, grapes in much of France struggled to ripen fully, and sugar was routinely added before fermentation in order to boost the final alcohol level (not to sweeten the wine). Napa Cabernets back then were around 12 to 13 per cent.

But by the early years of this century, 14.5 per cent became almost the norm for Bordeaux and a virtual minimum for Napa Valley wines, which sometimes reached 16 per cent. Was this because summers were getting hotter and fermentable sugar levels in grapes were rising as a result? This indubitably played a part, but was not the only reason. In California, more efficient yeasts and increasingly common virus-free vines were other factors, but there was another overriding one.

The Institute of Masters of Wine requires all successful examinees to produce a dissertation in order to qualify as an MW. Alex Hunt, purchasing director of Berkmann Wine Cellars, chose to research rising alcohol levels in California before being awarded those initials in 2010. He concluded that climate change played a much less important part than had been supposed, and that just as important were prevailing fashions in consumer taste — and the related fact that the then-powerful wine critics seemed to favour potent wines, garlanding the super-ripe 1997 vintage, for instance, with praise. Growers started deliberately leaving grapes on the vine longer in order to ripen phenolics such as tannins, so that the wines they produced tasted smoother and sweeter (in line with changes in diet). Obvious acidity or the leafiness associated with less-than-fully-ripe Cabernet were at the time viewed as undesirable.

As a result, these overripe grapes had the potential to reach such high alcohol levels that, when he quizzed more than 100 California winemakers, Hunt found that 88 per cent of them admitted adding water to their musts, as the stage between grape and wine is known. This has been officially allowed in California since 2002 if the vintner is worried that the must is so sweet that the yeast designed to convert the sugars into alcohol will give up.

Almost half of them also admitted to resorting to one of the two, much more expensive, physical means of dealcoholising musts, reverse osmosis and spinning cone techniques. Most wine producers keep very quiet about these ploys, but the estimable Ridge Vineyards in California is a noble exception. Since 2011, everything that goes into its wines has been listed on its distinctive labels and water has been included for vintages 2012 to 2018, 2021, 2022 and 2026. No one would accuse Ridge wines of being unbalanced or dilute.

Today’s producers and consumers have been turning away from alcohol and are actively looking for fresher wines. In fact, it has become something of a fetish. (I have tasted wines up to 15.5 per cent alcohol that taste delicious and are perfectly well balanced, but I’m highly unlikely to remember, with the next morning in mind, to drink less of them.) The year after Hunt qualified as a Master of Wine, celebrated sommelier-turned-winemaker Raj Parr and Sonoma Coast wine producer Jasmine Hirsch began a movement called In Pursuit of Balance to showcase lower-alcohol wines. By 2016, they reckoned they had been successful enough to abandon their series of tastings — and it is now very clear that the tide has turned, not just in California but virtually worldwide.

In my experience, although most wine drinkers today are actively seeking less alcohol, they want no sacrifice of flavour. So what steps can producers take to deliver what the market wants? M Chapoutier of the Rhône valley, for example, deliberately pays a premium to growers who deliver lower-alcohol ingredients for its Côtes du Rhône. In the winery, the use of cultured yeasts specially designed to deliver less potent wines has been increasing.

But, as in virtually every aspect of wine production currently, the focus has shifted from winery to vineyard, and alcohol reduction techniques are no exception. The obvious thing to do is to pick grapes earlier, but in our warming world conventionally measured harvest dates are already weeks earlier than they used to be. (In Burgundy, where the harvest has traditionally occurred towards the end of September, some growers picked as early as August 10 this year.) If grapes are picked too early, sugar levels may be low enough to yield wines at 12 or 13 per cent, and have sufficient acidity to be refreshing, but they may not have built up enough flavour to be satisfying. I seem to come across quite a few fashionable Australian reds that may not have much alcohol or colour, but don’t have much grunt either.

The problem with several viticultural ploys is that they take years to be effective. In Napa Valley, for example, there is a trend to play with the direction of vine rows so that bunches are not subjected to the harsh midday sun, but vineyards are replanted only every few decades. The same is true of planting later-ripening or heat-resistant clones, rootstocks and/or vine varieties. Growers are playing around with the way their vines are trained, but that may involve completely redesigning their trellis system.

One rather more immediate tactic is to change what happens in the vineyard on an annual basis. The aim of “canopy management” used to be to expose grapes and a maximum number of leaves to as much sunshine as possible. Today it makes more sense to protect grapes from sunburn while carefully calculating just how many leaves are needed for optimal rather than maximal photosynthesis — a tricky balance that is sometimes summarised as aiming for “dappled sunlight”.

In the big, bold wine era, it was thought that the lower the yield, the better, as it would result in concentrated fruit. Today, yields are being consciously increased by even the most quality-conscious growers in an attempt to slow down ripening. The winter or spring pruning process, which determines how many potential buds are left on each vine, has therefore become an increasingly delicate one.

And then there is the whole question of irrigation. In much of Europe, it’s forbidden, so growers are having to cope with increasingly common droughts that result in small, concentrated berries. Outside Europe, however, the precise timing and amount of irrigation can be valuable tools in slowing the ripening process and therefore reducing the final alcohol level of the resulting wine.

Cover crops can compete with vines for nutrients and therefore slow ripening, and in general organic and biodynamically grown vines tend to ripen earlier with no loss of quality in the finished wine. It was notable how many of my lower-alcohol recommendations here were grown biodynamically.

Wine drinkers in the UK specifically may have noticed a perceptible decline in alcohol levels in some of the mass-market brands. This has been a deliberate move since the 2023 introduction of a system that links duty rates to alcoholic strength, so there is a real incentive on the part of brand owners to offer supermarkets lower-alcohol wines that can be sold at markedly lower prices than stronger ones.

This has meant that the bigger producers have had to invest in expensive reverse-osmosis machines, while the smaller ones may take advantage of the mobile versions offered by some outfits. The only problem, according to one importer of a popular Australian brand, is that the process tends to leave the weaker wine tasting hollow, so in order to fill the gap, the wine is sweetened. A government tactic designed to make the population healthier by consuming less alcohol has therefore resulted in potentially increasing its consumption of sugar.

One more thing: the alcohol given on a label is only a rough guide. In the EU, it has to be rounded to the nearest 0.5 per cent of the true strength of the wine, and there’s a tolerance of 0.5 per cent, but in the US and Australia, there may be a difference of up to 1.5 per cent between reality and what’s on the label. It used to be that producers tended to round upwards; today most are more likely to round down.

Tasting notes, scores and suggested drink dates on Purple Pages of JancisRobinson.com. International stockists on Wine-searcher.com

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