This ain’t your aunt petunia’s Prosecco! At the turn of the 19th century the tank method of secondary fermentation took over Prosecco and is now the norm, but before that we had Col Fondo. Col Fondo undergoes its secondary fermentation in the bottle, like champagne. Unlike champagne however the yeast is not disgorged, so the wine is left cloudy. The result is a sparkling with more of an apple cider like quality to it, with higher acidity and lower fizziness than what we associate with Prosecco today. Think of it as a cousin to Pet-Nat.