Sparkling wines made using the Ancestral method have been a recent trend on the marketplace. They more commonly go by the term Pétillant Naturel (or Pet Nat for short). Unlike traditional method sparkling wines that undergo a full primary and secondary fermentation, Ancestral method wines are produced by stopping the first fermentation before it is complete. A calculation is done to determine how much remaining sugar is needed to create the ideal amount of pressure in the final wine. The partially fermented wine is then bottled. The wine will then continue the fermentation process. Yeast can struggle to complete the fermentation process as sugar and yeast nutrients dwindle while the pressure and alcohol increase. It is not uncommon for the fermentation process to stop early, which can create significant variation between each bottle. The resulting wine will have some residual sugar. The winemaker can also decide if they want to remove the dead yeast cells or send them to market with a slight turbidity. They can also have initial aromas of volatile acidity, which show up as acetone (nail polish remover) or kombucha. This is a common characteristic of natural wines. Some find these aromas desirable while others find them very off putting, especially when they overtake the other aromas in the glass. There are no set production standards for wines made using the Ancestral method.
This week, I drank a 2020 Lone Madrone Pet Nat made with 100% Chenin Blanc. This wine has a pale lemon color and persistent streams of tiny bubbles rising to the surface. There is also a layer of sediment that has collected on the bottom of the bottle as it has chilled in my fridge. There are aromas of lemon pith and lemon juice, green apple, white pear, wet stone, and yogurt. This dry wine has slightly viscous texture and low alcohol. The sparkling character is light and refreshing but definitely less than a traditional method sparkling wine. There is a significant level of acidity but not harsh. This wine is very reminiscent of a fermented cider and makes a great alternative to drinking beer! The freshness of this wine was surprising to me because these wines are intended to be consumed while they are young. This bottle has been in my collection for a couple years and has held up nicely.
-TheLooseTannin
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