A friend has just given me a bottle of Muscat from Rutherglen Estates. In the bag with the bottle was a copy of their Spring 2010 newsletter that included the following article on the making of white wine. I thought I’d share it with you.
White wines require attention to detail.
Step one is the pick date, which is vital … and this window is small. It is important to pick the grapes when their varietal flavours are at their optimum, and in the spectrum we are looking for. For example, we pick Fiano when the ripe fruit flavours have started to appear, but before the flavour starts to broaden and the natural acidity drops out.
The grapes must be picked when the temperature is at its coolest, usually on dawn. We then crush and press the grapes as gently and quickly as possible to avoid any oxidation, so that we preserve the maximum amount of flavour and freshness.
After pressing, the juice is chilled and any solid grape matter falls to the bottom of the tank. Usually with white wine we only use the cleanest juice, although we do add some of these solids to wines like our VRM, as they add texture and mouth feel. We then ‘rack’ off the clean juice and ferment it as slowly as possible to help maintain freshness.
After fermentation has finished, most of our white wines are cleaned up and prepared for bottling. Pinot Grigio and Arneis are two exceptions, as they mature on the yeast lees. When fermentation has finished the yeast dies and falls to the bottom of the tank. For theses wines, we pump the lees over the top to mix them back in every two weeks. This helps build texture into the mid-palate without losing too much varietal definition. Our aim is to produce good food wines, so the trick is to get the balance right.
Final processing involves ensuring they are heat and cold stable, which means they won’t drip a deposit or form a haze in the bottle, if the wine is stored in hot or cold conditions. As you can imagine, consumers do not like to find a deposit in their wine. We also add some fining to the wine to take away any bitterness on the back of the palate. These finings may be skinny milk or isinglass (which is a fish product), which fall out of suspension once they have reacted with the bitter phenolic compounds, and do not remain in the wine.
The last step is to filter the wine to ensure it looks great and make sure the sulphur dioxide levels are right. When we are happy with the white wines, we add the finishing touches to prepare them for bottling. All this requires tests and trials in the lab, as well as fastidious work in the cellar when oxygen is avoided at every step. After bottling and giving them time to settle, it is time to enjoy the new release whites!
Reproduced with permission from Rutherglen Estates, ReVive Newsletter, Spring 2010 edition.