Search This Blog

Wednesday, July 16, 2014

Making Good Wine: Fermentation Part One (White Wines)

Once the grapes arrive at the Cave there is one simple step. The picking container is placed in a cooling device. In this case a salvaged freezer or refrigerator and the grapes chilled. This takes the pressure off and provides time to record information in the vintage book, clean any equipment that has been used and have a meal and/or cup of hot liquid and plan the next step.

White Wine
The initial step with Whites is the destemming process. Just a quick run through the crusher/destemmer and into the refrigeration unit for 16 to 20 hours of cold soaking. This seems to be the optimum time to obtain some of the flavour from the skins to enhance the final wine. Various makers try various levels of skin contact to obtain different results. An individual choice based on experience, type of fruit and the end result being targeted. Grapes with a higher sugar level will cope with more skin contact. Some makers go for 36 hours to produce long aging wine.

One variant is to not de-stem but press as whole bunches being careful to press gently so as not to break the stems. This leads to a clear juice with the lowest possible phenol levels and produces a wine that is finely flavoured and structured.

After cold soaking Potassium Metabisulphite can be added to reduce the risk of oxidisation and infection by unwanted yeasts and bacteria. Fruit quality dictates the level of sulphuring. With good quality fruit as little as 25 part per million (ppm) will work. With damaged fruit 50 ppm is safer. It should be noted that some producers add sulphur at the crush for extra safety.

It is possible to make white wine without preservative but it requires very special handling and specialised equipment to exclude any risk of oxidisation.

 It can also be made without the special equipment by relying on Acidity, Alcohol and Tannins to protect the juice. The end result is best called a red drinkers white wine. It ages well but doesn't exhibit those fresh and gentle notes of a delicate white wine. But it is preservative free.

Pressing should always be performed slowly and gently. Just a light pressure over a long time. Using finger tip pressure is a good guide. This allows the pulp to settle into the gaps and the juice to escape. It also reduces the opportunity for the skins to tear and release unwanted phenols. This is where patience is required.

At HHF pressed juice goes straight into glass demijohns as a precursor to fermentation. Cotton wool is used in the neck of the demijohn. The demijohns are kept under refrigeration at 10 C.

Once the wine is sulphured and pressed it should be rested for 24 hours to allow the sulphur to perform its function.

Next: Making Good Wine: Fermentation Part Two (White Wines)

No comments:

Post a Comment