Bottling sparkling wine starts with a riddle - literally. To create sparkling wines' distinctive bubbles, they're sealed into the bottle sugar and yeast. While converting the sugar into alcohol, the yeast produces carbon dioxide. The result is fun but the yeast residue is a bit unsightly. To get rid of it, bottles are placed neck down into racks and gradually turned and tilted, a quarter-turn at a time until the sediment makes its way into the neck of the bottle, a process that can take two months.
Now that the yeast is in the top of the bottle, it still has to get out. The bottles you see in the photo above have just been removed from a freezing solution - you can see the ice and yeast residue solidified in the neck. The caps are removed, the pressure inside forces the ice plug out the top or "disgorged." Finally the "dosage" (a little bit of sugar dissolved in wine) is added before the final cork goes in. The amount of sugar controls the wine's final sweetness.
