Research reveals health benefits of organic wines are over-hyped
Organic wine may be served with claims of greater health benefits and fewer toxins, but the research says otherwise, writes Larissa Fedunik.
Organic wine advocates claim that by drinking organic wine, consumers can avoid toxins and enjoy the benefits of higher levels of antioxidants. However, several recent studies comparing organic and conventionally produced wines suggest that the health benefits are more hype than substance.
The organic wine market is relatively small, but consumer and retailer interest is growing by the year. The total domestic retail and export value of Australian organic wine grapes and wine has more than doubled in the last 10 years.
The theory that hangovers and headaches can be avoided by choosing organic has also been steadily gaining in popularity. Organic vintner of Hunter Valley vineyard Ascella Wines, Geoffrey Brown, is convinced that hangovers are exacerbated by the toxins in conventionally produced wines. In conversation at the Hunter Food and Wine Festival last year, Brown recommended that wine enthusiasts limit their exposure by going organic.
Terrible toxins
The toxins that Brown was referring to are mycotoxins, toxic chemical products produced by fungi that colonize crops such as cereals, coffee and grapes. You may have heard of mycotoxins before — the blogosphere was abuzz a few years ago after high levels were discovered in cereal products. They were even heralded as “the new gluten”.
The main mycotoxin of concern in grapes is ochratoxin A (OTA), which has immunosuppressive properties and is a possible carcinogen. In the European Union, regulations control the maximum permitted levels of OTA in food and wine. Australia, however, has no such limits. This begs the question: should we be actively seeking to minimise our exposure — and will switching to organic wine make any difference?
There have been a handful of published studies comparing OTA contents in organic versus conventionally produced wine. Brown pointed me in the direction of a 2003 study in the Journal of Wine Research which compared conventional red wines with organic red wines. The researchers found that OTA levels were up to three times higher in the conventionally produced wines. However, it’s important to note that OTA was present in all wines. More recent studies in The Journal of Agricultural and Food Chemistry and Food Chemistry have found no significant differences in OTA levels in conventional and organic wines — and all wines tested contained far lower levels than the maximum OTA limit.
Dr Giovanna La Torre, a research fellow at the University of Messina in Italy, published a 2016 paper which determined OTA levels in 55 different red and white wine samples from Sicily, all produced according to organic winemaking. La Torre says that they wanted to explore the influence of new EU regulations on organic wine production, which restrict the use of artificial fertilizers, pesticides, herbicides and many vinification techniques. These regulations have also had an effect closer to home. All Australian exports going to the EU must comply with the regulations and require an Organic Produce Certificate from an authorised certifier.
La Torre’s research group detected OTA in all of the wines they tested, but always at much lower levels than the EU limit (0.5 micrograms/L). The organic and conventional wines had similar OTA levels. La Torre says that one of the paper’s aims was to let the consumer know that
‘…even a “totally organic” wine may contain ochratoxins.’
The current consensus is that such low levels of OTA present a very low risk of any ill-health effects. The EU Scientific Committee on Food has set the maximum limit based on tolerable weekly limits of OTA consumption to minimize any risks and a paper published in the journal Food Control declared
‘…there is no reason to be alarmist [about OTA levels].’
If you are really concerned about minimising OTA intake, you could make your tipple of choice a Sauvignon Blanc, as opposed to a Cabernet Sauvignon. This is because the majority of the total OTA content, if it is present in the grapes, is bound to the skins and stems, which are discarded in white wine production but remain in reds.
But rest assured that scientists are confident that OTA doesn’t pose a significant health risk. In particular, Australian wines consistently show low OTA levels. Incidentally, there is no established link between OTA and hangovers, although this is a highly under-researched area. Even the notorious sulphites (chemical compounds which naturally occur in wine and are commonly blamed for headaches) have never been the subject of a wine-induced hangover study.
Antioxidant activity
Many of us justify indulging in wine because of its high levels of antioxidants, which are believed to be anti-carcinogenic. Associate Professor of Chemistry Paul Prenzler has carried out extensive research into wine’s antioxidant properties at Charles Sturt University’s School of Agricultural & Wine Sciences.
Prenzler dates the global interest into the potential health benefits to media coverage of the “French paradox” back in the early 1990s. When French cardiologists observed that national levels of the disease were low in the wine-loving nation, red wine was first proposed as a health-improving beverage.
“It was a turning point in the study of wine as a functional [health-beneficial] food,” says Prenzler.
Red wines are 20–50 higher in antioxidants than white wines, but the waters are murkier when it comes to differences between organic and conventional wines. Organic vintner Brown may believe that his wines have higher antioxidant levels, but studies in Food Chemistry and the Journal of Food Science found that any differences are not statistically significant.
Prenzler’s research team has published several papers assessing Australian red wines in terms of their antioxidant activity, a means of comparing the antioxidant effects of phenols (chemical compounds which impart sensory and nutritional value). He explains that it is very tricky to categorically determine the factors which increase antioxidant activity in wine, although research has shown that climate and vinification processes are influential.
Furthermore, Prenzler says:
“It’s difficult to draw a straight line from the chemical measure of antioxidant activity to human health benefits. Antioxidant activity doesn’t necessarily put a number on it.”
So it is possible that antioxidant activity may not even be that important a factor in quantifying health benefits, regardless of whether a wine is organic or not. Mycotoxins are unlikely to pose any health risks — and as for minimising your hangovers, moderation, rather than going organic, is probably the name of the game.
