According to McWilliam's, its Balance wines are 8 per cent to 8.5 per cent alcohol, one-third lower than regular wine. They are also one-third lower in kilojoules (ranging from 228kj for its sparkling wine, 264kj for its semillon sauvignon blanc, and 324kj for its shiraz).
And Australian producers are now expanding the sale of low-alcohol wines to the weight-conscious citizens of North America and Britain.
Last year, McWilliam's became Weight Watchers' first light-wines partner in Britain, and last week Australia's Accolade Wines and Treasury Wine Estates announced new low-cost, "light" wine products for Weight Watchers in the United States.
According to one of the wine companies, one in five Americans, mainly women, are on a diet. More than 70 per cent of Australian women are also seeking to control their weight, and wine is their alcohol of choice.
Light wines can be made naturally by harvesting grapes early. The quantity of sugar in the fruit translates to the level of alcohol in the wine. These wines have around 25 per cent less alcohol and still retain reasonable sensory qualities.
However, people may compensate for the saved kilojoules from light wine by eating extra food.
To reduce kilojoule (energy) content by a third requires industrial processing after the wine is made. The taste of early wines produced this way met with derision.
Since then, reverse osmosis techniques have been perfected to pressure-filter wine through a fine porous membrane. This method uses less heat than earlier technologies, preserving flavour.
At first glance, providing "diet" wine appears socially as well as fiscally responsible. As long as consumption remains managed under a weight-control programme, drinking light wine may not have any side-effects.
Australia's National Health and Medical Research Council (NHMRC) alcohol guidelines define one standard glass of white wine as 100ml, containing 11.4 per cent alcohol, and the same volume of red wine containing 13.5 per cent alcohol. The maximum safe daily intake for women and men is two standard glasses.
But, unlike with light beer, which has long been available, the NHMRC has no consumption guidelines for light wine. This, alongside aggressive marketing could spell danger for consumers.
Changing the energy content from 372kj for a standard sparkling wine to 228kj is a negligible energy saving (equivalent to half an apple), yet having wine badged as "light" or low kilojoule may give people trying to control their weight the impression that they can either eat more food, or drink more wine.
People may compensate for the saved kilojoules from light wine by eating more.
Similar problems have been observed with the marketing of foods badged as low-fat, which are thought to contribute to the obesity epidemic.
A second, related health concern is that light wines may encourage more drinking, fuelling an overall increase in alcohol consumption in a country that already drinks too much.
Finally, it may encourage overconsumption of a product that has negligible nutritional value. Given these concerns, there's an urgent need for consumption guidelines on "light" wines.
As you raise a glass, be aware that diet wines may not be without their own side-effects.
Julie McIntyre is a lecturer in history and a wine studies scholar at the University of Newcastle.
theconversation.edu.au
