Winemaking is a balance of science and art. There is a procedure and then there is a ‘feel’ – an instinct one develops – for how and when things are done.
Mt Billy is a small-scale, artisanal vineyard. This means we can afford special attention to the details of winemaking. We believe the details make all the difference. You can read here about our process and see what sets Mt Billy apart from large scale producers.
When fruit flavours, seed colour/flavours, and mouthfeel of grapes tasted are optimally balanced, ‘with an eye to’ the desired wine taste profile, we then hand pick our grapes in the cool of the maritime morning at Victor Harbor.
Red Wine Making
The bunches of red variety grapes are harvested, with some destemming. Special care is taken to minimise berry crush, to achieve maximise fruit character in our very small batch ferments. Varying volumes of whole bunches are added to the ferment to further maximise flavour. Next, we cold soak for 4-5 days until a ‘wild yeast’ ferment begins. At this stage the best variety specific cultured yeast is added.
We gently hand plunge the cap twice daily until the primary ferment ends, keeping the cap of skin, seeds, and stems wet until it sinks, usually after 29-50 days of maceration.
Industrial winemakers typically use vigorous, large volume ‘pump overs’ that ‘bruise’ the wine, and often only have 4 -5 days of wine/skins contact.
Ferments ‘free run’ for as long as the temperature remains below 30 degrees Celsius. Refrigerated stainless steel plates are used to regulate the fermentation temperature. The wine is then pumped from the fermenters into a stainless-steel tank, including the pressings, which is the wine that was pressed out of the grape solids left in the fermenters. At Mt Billy, we add this small step as it yields wine with better structure and mouth-feel. The pressings also assist with preservation, so our wines need to be only minimally sulphured.
Many large commercial producers ‘spread around’ the pressings from stronger reds to bolster the structure of softer reds.
The blended wine is pumped into barrels to complete the malolactic fermentation (MLF). Once the MLF is finished, wines are minimally sulphured to prevent spoilage over the 12-24 month barrel maturation period. Once matured, wines are bottled and ready to be enjoyed.
White Wine Making
The white grapes are handpicked when we think the fruit flavours and mouthfeel are at their best, balanced with the aim of minimalising the final wine alcohol volume.
The bunches of white grapes are chilled immediately after harvest. The grapes are pressed, with the juice running into stainless steel fermenters. A “wild yeast” ferment develops naturally under these conditions. The temperature of the ferment is kept very cool to maintain the delicate aromatics and flavours of the grapes. This primary ferment continues for 2-3 weeks.
The wine remains in the stainless-steel fermenter for another 2-3 months. The solid residue from the grapes, (the lees), is stirred weekly during this time.
Typically, only small-scale winemakers take this extra step. At Mt Billy we believe stirring the lees is worth the effort, as it yields wine with enhanced texture, structure, and mineral acidity.
Finally, minimal sulphur is added to the wine before bottling.
Large scale producers generally use higher levels of sulphur.
The Role of Sulphur
Sulphur is a multipurpose product. In low concentrations, it is used in both ‘organic’ vineyards and large commercial ‘non-organic’ vineyards as a fungicide. It kills the naturally occurring airborne fungus that causes powdery mildew – a disease that destroys leaves – hence it stops photosynthesis, and grapes don’t ripen.
In winemaking, Sulphur’s anti-oxidation and anti-microbial properties serve to inhibit, or destroy unwanted ’feral’ yeasts and bacteria that can get into wine during fermentation. When used minimally – 36 parts per 1,000,000 at wine bottling – it provides consumers with the confidence that they do not need to store their wine purchase at a constant 14 degrees Celsius, as is required to keep ‘Sulphur free/preservative free’ wines ‘healthy’ for only around 12 months.
Minimally sulphured wines will remain pleasantly, healthily drinkable for many years after purchase and not cause ‘sulphur headaches’ experienced by some people.