The juice now separated from the skins, sulphured and rests for 24 hours in demijohns. The prior skin contact will evolve in the flavours of the finished wine.
At this time it is possible to clarify the juice by continuing to chill but choosing not to clarify leads to a richer wine.
Now is the time to perform some testing. Firstly sugar levels
using either S.G. or as it is done at HHF a refractometer. Now that
all the grapes are combined and everything standardised the reading
is accurate. Whether sugar is to be added really depends on the grape
variety. Some like Hunter Semillon will do fine at 18.5 Brix (alcohol level of 10.5%). As a general
rule at HHF anything above 20 Brix is fine as long as the fruit is ripe. Although there is more comfort in 21.5 Brix. At that level the
wine has some body and keeps well without too much sulphur.
The second test which adds value is the pH test using either pH
papers which are cheap but not as easy as a meter, although the
meter needs to have calibration checked when unused for a period. Various guides recommend a lower level of 3.0 and an upper level of 3.3 through to 3.5. A
goal of 3.25 is ideal and adjust only with Tartaric acid. 3.5 is
the absolute upper limit but with 3.25 much less sulphuring is
If it has been a dry or drought year then yeast nutrient is
critical. But don't use a lot and only add it after one third of the
way into the fermentation. add the last yeast nutrient at two thirds
through the fermentation and none after that.
While the testing is going on a bit of juice has been taken and
the sample container sits in a bowl of hot water to get the sample to
40 C at which point the yeast is added. When the yeast commences
fermentation a little cold juice is added until the temperature drops
by no more than 10 C. This is left until the fermentation fires up
again and then more cold juice is added and so on until the
temperature of the yeasted juice falls to within 10 C of the main
batch of juice. It is then gently added. Now wait until the airlock
begins bubbling, usually about 24 hours.
There is a school of thought that the airlock should now be
removed and replaced with cotton wool to allow the gases to vent more
easily, especially any off aromas.. At HHF both methods have been used with success. although an
airlock is safer.
The demijohn must now be slowly cooled to between
10 and 15C. This is done by placing the vessel into a refrigerator
with an adjustable thermostat. The cooler fermentation results in the production of more fruity esters.
Test the sugar levels of the wine every day to follow the falling
levels. At the same time shake up or stir the sediments in the
fermentation container. This will add a complexity to the final wine.
When two thirds of the sugar has expired take the demijohn out of the
cooling chamber and allow it to finish at a higher temperature but
not more than 30 C, 27 C being ideal. This serves two purposes. Firstly, helps prevent a
stuck fermentation and secondly, adds another dimension to the final
wine. All these manipulations do really add complexity into the wine
some of which may not be apparent until the wine has aged a few
At this two thirds point when the wine reaches the ambient
temperature, usually about a day, it ideally should be racked into vessels with
as little head space as possible to finish fermentation. At the end
of fermentation allow 30-40 days for the sediment to settle and then
rack into clean containers. Getting it off the gross lees is
important to prevent the production of Hydrogen Sulphide from the dead yeast cells.
When racking off gross lees is
also the best time to add oak chips. Anywhere from 0.5 to 4 grams/litre although 5 grams
has shown a good result in Semillon. The amount of Oak really depends on the fruit ripeness. More ripeness handles more Oak. Don't use Oak on Sauvignon Blanc or Traminer as they have strong spicy aromatics of their own.
It can be racked again if desired although at HHF the least amount
of handling has produced the best results. If lees really build up
then a racking is a good idea but if there is only a fine film it is
Bottling is best done during the period leading up to no moon and
ideally in the cool of mid to late Winter. The experience here is no
sediment problems even after a number of years in bottle. Natural
settling is far superior to fining or filtering.