First fermentation

The same yeast as for second alcoholic fermentation (AF) is used to avoid killer factor problems. Nutrients and bentonite may be added.

The optimum fermentation temperature is 15°C. If temperature is too high (i.e. 18 - 20°C), alcoholic fermentation can be too rapid producing wines that lacks finesse. If the temperature is too low (<10°C), the wines can be grassy & herbaceous.

Many producers carry out the Malo-Lactic Fermentation (MLF) as this reduces acidity, alters flavour (reduces fruit flavour), and increases stability (MLF in bottle can render the wine almost impossible to riddle).