It was once a tiny voice in the wine wilderness.
Now it's becoming a roar.
The organic and biodynamic wine movements, with their return to a simpler time before winemakers needed a couple of science degrees to understand the chemical additions they perform, are proving a boon for vegetarian wine drinkers.
Those shunning additions to their wines, notably the use of animal-based products, are becoming the vegetarian's new best friend.
Conventional winemakers, too, keen to promote themselves as sustainable, minimal interventionists are now openly marketing their wines as vegetarian and vegan friendly.
Barossa Valley-based wine producer, Yalumba, has 40 wines meeting the vegan criteria.
So, what is a vegetarian/vegan wine?
There is no legal definition, but basically it's a wine in which no animal or fish products have been used. Many vegetarians give a dispensation for milk and dairy products.
Vegan friendly wines, on the other hand, avoid all animal products, including dairy and eggs.
Wine producers traditionally employ a range of animal-related products including eggs, milk, gelatine and isinglass (a type of gelatine made from fish bladders) to fine or clarify their wines.
There's nothing new about it. The products have been used in cellars around the world for centuries and winemakers say that not only are the products effective but no traces end up in the finished wine.
"Impossible to prove," counters wine writer Martin Field, who is also a vegetarian.
"Some vegetarians and especially vegans object to the fact that such ingredients are used at all, usually on the grounds that a creature had to be killed to obtain the substance in the first place."
But isn't wine made from grapes?
Yes, but under Australian wine law there are around 50 additives and processing aids that winemakers can legally use.
It's those additives that are now in the spotlight.
Jen Pfeiffer is a winemaker and a vegan.
She stresses she isn't a "philosophical vegan", just someone with a distaste for meat, eggs and a lactose intolerant, and while some of the wines she makes at her family winery, Pfeiffer Wines in Rutherglen may not strictly fall under the vegan umbrella, many do.
It's not that hard.
"I think vegan wine can be made without too many changes to a winemaking technique," she argues. Using clay-based bentonite instead of egg whites can produce a similar result while "gentle extraction" methods will soften tannins (yet another winemaking use for animal-based fining agents).
The quality and pedigree of the finished wines shouldn't be an issue.
"Pfeiffer riesling has been vegan friendly for over 10 years now," explains Jen Pfeiffer "and Christopher's VP (vintage port) has been suitable for vegans since the 2008 vintage.
"Both wines have strong pedigrees."
Some winemakers suggest their vegetarian and vegan wines taste better with more flavour and texture than their competitors. The jury's still out. Certainly, fining the daylights out of a wine can leave a wine running empty on flavour.
Whatever it is about these wines it's starting to show in sales.
Vegetarian and vegan-friendly wines are becoming big news, especially in Europe where they are closely associated with the organic and biodynamic food and wine movements. Major supermarkets lead the way.
According to media reports, vegetarian wines now make up more than 50 per cent of wines listed at Tesco, Britain's biggest supermarket chain. Vegan wine numbers are a little less.
Here in Australia, the Veg Network Victoria (www.vnv.org.au) lists a surprisingly large number of Aussie wines, from big companies and small, meeting vegetarian or vegan criteria.
Natural wines, the new darling of the alternative wine set, are also bringing in the converts.
At best a loose term, natural winemaking generally refers to those who add little or nothing to their wines: no pesticides, herbicides, cultured yeasts, enhancers, bags of oak chips, tannin, acid and, importantly for vegetarians, no fining or filtering which can manipulate flavour.
The Natural Selection Theory (NST) (www.naturalselectiontheory.com) is a group of four South Australian so-called "natural" wine proponents.
Member James Erskine of Jauma Wines in the Adelaide Hills doesn't advertise his wines as veg or vegan-friendly but his philosophy of "adding nothing, removing nothing" ensures they are.
He recently visited a new Adelaide pizza restaurant, Ettica that was stocking only vegan wines.
And so it goes on.
Yalumba winemakers originally pursued vegetarian and vegan wines as a way to be smarter about their winemaking. And what do you know? They discovered a big new audience of vegetarians and vegans hungry for their wines.
It was, says chief winemaker Louisa Rose, a revelation.
"We have had the most incredible response, mainly through information on our internet site," she says. "We couldn't believe it!"
There is, however, one Yalumba wine style yet to go vegan and that's sparkling wines.
But they're working on it.