What is Pet Nat?
Petnat is an abbreviation for pétillant naturel or "naturally effervescent". Petnat reverts to an ancient method to obtain bubbles. This is the méthode ancestrale, also known as the méthode rurale.
It seems that this method was even there before the traditional method. The story of this method begins with an explosion. The big bang of the bubbles. Logical, because no one had planned for these bubbles. People thought the fermentation was done and bottled the wine but when the temperature went back up in the spring, the fermentation continued in the bottle. Back then, we are talking about the 16th century, bottles were not as strong as they are today, so 1+1 = a fireworks show of exploding bottles in the cellar.
Nowadays, things are different, at least in stronger bottles. It is still difficult to control the process, because yeast has its own will, which you can influence mainly with temperature. The wine is bottled before the first fermentation is complete, producing carbon dioxide that cannot escape. Unlike Champagne, petnat is not disgorged and is (usually) bottled unfiltered. Nice and minimalist.
Where does petnat come from?
Petnat is not tied to one region - it can now be found all over the world - but the method ancestrale has its origins in Gaillac, southern France. There are a handful of AOCs that prescribe the method ancestrale or some variant thereof
The winemakers here - exceptions aside, we are still in the wine world - know the method ancestrale like the back of their hand. Usually the wines are disgorged to get a more stable final product. The opposite is true of "new" petnats, which are not disgorged or filtered and the cloudy appearance is actually part of the style.
And we find this style in abundance in the Loire. Not surprisingly, because the Loire is the Valhalla for natural wine. And petnat, of course, fits perfectly into this picture. If you are a winemaker of hardcore natural wine and you want bubbles, then the method ancestrale is the way to go.
In 2007, AOC Montlouis-sur-Loire introduced a new term "pétillant original" (the term 'naturel' cannot be used in French AOC legislation - a story for another time). It's not really original, of course. Moreover, the law requires that the wine be aged for nine months on the lees and be disgorged. Two things that Loire winemakers don't usually do. Oh the irony.
In Italy, method ancestrale is known as col fondo, which literally means "on the bottom" referring to the yeast cells that remain in the bottle. Have you ever tried a prosecco col fondo? (I haven't, but I'm ferociously curious). The sparkling wines labeled as frizzante are also often made by the method ancestrale.
What does petnat taste like?
Petnat comes in all styles: white, red, rosé. Most are dry, because fermentation continues in the bottle as long as there is sugar. And cloudy, because the wine is not filtered. The pressure in the bottle is usually 2.5 to 3 bars, about half that of Champagne. A frivolous bubble, lightweight and very refreshing - I can tell you. This is also due to the alcohol content which is usually under 12%.
An article in The New York Times compared petnat to a "session," a term in beer culture. Session is described as beer with low alcohol content. This allows you to drink more of it (for a session) without getting drunk.
Not new, but hip
So Petnat is 500 years old, but it totally fits in with today's times. They are often artisanal wines (small circulation), made naturally (without sulfites) and easy to drink. The bottle is empty before you know it.