Pet who? – your 101 guide to pétillant naturel

Have you ever had a Pétillant Naturel? Also known as a “Pet-Nat”?

Pet not? Pet-who? Gnat-what? Fear not! This is a super-exciting sub-category of sparkling wines and we’re here to explain everything about it! But, in order to have a fuller understanding on what makes a Pet-Nat different from other bubbles, we should quickly unpack some of the other sparkling winemaking processes. Each creates a unique style with different levels of carbonation and texture.

A crash course on Sparkling Winemaking

Wine at its most basic is grape juice that undergoes fermentation. Fermentation is the process through which yeast eats the sugar in the grape juice to create alcohol (thank you yeast) and CO2 – that’s our bubbles! If we want to create a still wine, we can ferment in an open vessel and the CO2 goes off into the air – simple enough. When producing a sparkling wine the goal is to harness those bubbles one way or another. While so easy to drink, getting a sparkling wine right requires some of the most technically complicated production methods in the wine world. There are many production methods, each capturing the CO2 in the wine differently. We’ll quickly run through the top two and then dig into our cool Pet-Nats.  

The most popular and well-known is ‘Méthode Champenoise’ (Champagne Method) a.k.a. the ‘Traditional Method’.

The grape juice undergoes two rounds of alcoholic fermentation in this method: the first, in which a still wine is produced in a larger fermentation vessel; and the second, aptly named Secondary Fermentation, triggered in the bottle, with the help of added yeast and sugar, inside of which our bubbles are created – as a byproduct of fermentation – and trapped. Once the yeast eat all the sugar and ultimately run out of food, the yeast cells die. (Sad.) But in the afterlife they get a new name – lees [ leez ] and it’s their long-term interaction with the wine that creates much of the texture and flavours we come to expect from a traditional method fizz. The lees are ultimately removed from the bottle in a process called disgorgement, making for a sediment-free sparkling wine. Additional sugars – called dosage –  may be added as a last step before the bottles rest and are sold. Beyond Champagne, many sparkling wines are produced this way, including French Crémant, Cava, Franciacorta and even most English Bubbles.

Also quite common is the ‘Tank’ or ‘Charmat Method’.  This is how most Proseccos are produced but, again, this production method is not exclusive to the region. Here, both primary AND secondary fermentation (with added sugar and yeast) take place in special pressure-resistant tanks, and the resulting sparkling wine is filtered and bottled. There’s little – if any – contact with the lees which explains why these wines are usually lighter and less complex. Again, dosage is optional, but extremely common. 

So what about Pet-Nat?

Pet-Nat’s (finally!) are produced via the ‘Méthode Ancestrale’ (Ancestral Method):  a single alcoholic fermentation is stalled about halfway through by dropping the temperature of the wine to a level at which yeast cells go dormant. The wine is then bottled (it might undergo a period of ageing prior to bottling). Then, as the temperature of the wine rises back up, the yeasts wake up and complete the conversion of sugar into alcohol, creating our CO2 directly in the bottle. However as this fermentation was not exclusively dedicated to the creation of CO2 and no additional yeast or sugar were added, the wines are often only lightly sparkling as compared to the other processes. Traditional Method sparkling wine is typically bottled at 6 bars of pressure, with most Pet-Nat’s averaging around 3 bars. [With that said, it still has significant  carbonation, it shouldn’t be shaken and caution should be used when opening!]

The technique is referred to as the Ancestral Method because it is believed to be one of the oldest forms of sparkling winemaking.

First mentioned in monastic texts in 1531 in Limoux, France, it predates Champagne pioneer Dom Pérignon. Given it’s early origins, Pet-Nat’s are often made naturally, with only minimal-intervention on the part of the winemaker. Most Pet-Nats are never disgorged and left unfiltered with sediment and lees (dead yeast) commonly found in the bottle. They’re harmless! And, as mentioned above, they help develop texture and new flavours in the wine as it continues to age. No dosage is added, so the wines are often quite dry and fresh! You’ll also note that many Pet-Nats are bottled with a crown (beer) cap. (the lower pressure inside the bottle doesn’t require the cork and cage of other bubbles) Easy access. All of which appeals to the modern winemaker and consumer! 

In her book Natural Wine, Master of Wine Isabelle Legeron notes – “Although beautifully simple, it is, in fact, extremely tricky to get [Pet-Nat] right – bottle late and your sparkling will be flat; bottle too soon and you risk the whole thing exploding. It’s a precise art. Growers bottle the juice at a specific density to achieve the right pressure, alcohol and sweetness… Part of the joy, though, is the wine’s evolution in the bottle.”

Pet-Nat Revival

Today, the Loire Valley is teeming with Pet-Nat’s much thanks to the educational efforts of the Loire-based winemaker Christian Chaussard in the 1990’s. The Loire is also home to Bulles au Centre, the only French event exclusively dedicated to pét-nat. Pet-Nat’s have also become popular in areas with marginal climates. This style is more successful with lower ripeness than still-wines. Christopher Tracy and our friends at Channing Daughters on the east end of Long Island are some of the most notable pet-nat producers. They release as many as 10 different Pet-Nat’s each year including white, rosé, orange & red! Channing Daughters, along with Finger Lakes project Chëpika, by Master Sommelier Pascaline Lepeltier and local winemaker Nathan Kendal – have developed loyal followings in the New York City market. Austria is another pet-nat hotbed, with exciting projects such as Fuchs & Hase, a collaboration between winemaking couples Alwin & Stefanie Jurtschitsch and Martin & Anna Arndorfer. We’re even seeing a new wave of Italian wines, such as “Col Fondo” Proseccos. Even red Lambrusco, getting the Methode Ancestrale treatment. 

Like your standard sparkling wines, we suggest serving Pet-Nat’s quite cold – whites at 6-8ºC, rosés or reds only slightly warmer.

If you notice bulky sediment in the wine, be sure to stand the bottle up while chilling. This way, most of the sediment will collect at the bottom of the bottle for when you pour. And skip the flutes! The aromatics and mousse will show better in regular wine glasses. 

We love that Pet-Nat’s punch above their weight in terms of quality, value-for-money and delight! Cheers! 

This is a guest-post by Dan Belmont

Dan is your neighbourhood wine & cheese raconteur. A native New Yorker, Dan fell in love with wine visiting the Finger Lakes wine region in New York State and has since worked as a brand ambassador and hospitality consultant for several notable Finger Lakes producers and represents the statewide industry in Europe. He is a former affineur, cheesemonger, & Education Manager of NYC’s famed Murray’s Cheese. He currently lives in London, where he developed the public education program at Bedales of Borough.