Chevalier Blanc de Blancs starts with a selection of white grapes: Colombard, Ugni Blanc, Chenin and other different grape varieties. The still wines made from these varieties are selected with great care to assure consistency in the finished wine. The cuve´e is carefully assembled by the winemaker and held in a chilled stainless steel pressure- proof vat Champagne yeast (a strain home grown by the Chevalier maitre de chais) and sugar are added to the vat. The yeast acts upon the sugar to create a secondary fermentation; the carbon dioxide gases which result, are retained in the sealed container as delicate bubbles. 4-5 times a week the cellar master uses a small propeller in the tank to gently swirl the wine: this provides contact with the lees (the natural grape sediment which precipitates during fermentation) At Chevalier, this process continues from 4 to 6 months in order to ensure distinctive and expressive flavours. When the winemaker determines that the maturing process is complete, the fermenting vat is cooled to -4°C to keep the newly created bubbles in solution, and the wine is filtered. A liqueur de dosage is then added to adjust the level of sweetness and the wine is bottled.