The Making of Barossa Shiraz

The Barossa Valley is renowned for producing wonderful and complex wines, and in particularly bold fruity Shiraz wines, which are successfully and eagerly exported all over the world. In order to make a great Barossa Shiraz wine, there are a few basic steps, Harvesting, Fermenting, Stabilizing and Clarification, and Ageing.   

Harvesting:  A great Barossa Shiraz begins with harvesting the best quality red Shiraz grape.  They are then pushed through a crusher or roller in order to split the grapes and release the juice.  Red grapes have clear juice, the red colour of the wine comes from the colours release from the broken skin of the grapes.  Therefore the juice is left in contact with the skins for a period of time during the fermentation process. 

Fermenting:  During the fermenting process of a Barossa Shiraz wine, yeast is added to the must (a combination of grape juice, skins, and seeds), which turns the majority of the natural sugars in the grape juice into alcohol and carbon dioxide.  This is known as primary fermentation.  In secondary fermentation, the juice is placed into vats (usually stainless steel vats) where the remaining sugars are left to ferment into alcohol over a period of time.  The juice must be stored in an airtight vessel in order to protect it from oxidisation.  The fermentation process is managed by the winemaker who monitors such factors as temperature, ration of juice to skins, the pressing technique, the length of fermenting time, and quantity of yeast added.  The fermented must is then pushed through a press so that only the juice remains and the skins and seeds are removed. 

Stabilizing and Clarifying:  is where excess minerals such as potassium tartrate are removed.  These minerals are like fine grains of sand and are sometimes know as wine crystals.  They are removed otherwise they will precipitate out of the wine at a later stage.  Clarifying a Barossa Shiraz involves fining, racking and filtration.  Fining removes tannins from the wine and removes microscopic particles which could cloud the wine if not removed.  The winemaker carefully chooses exactly which fining agents are used.  Some fining agents include gelatin, milk proteins, egg whites, egg albumin, and skim milk powder.  Racking involves the process of siphoning the wine from the lees, which is the deposits of residual yeast that remains from the fermenting process.  The wine is transferred into clean barrels, this allows clarification and assists in stabilization of the wine.  This racking process is repeated several times. 

Ageing:  a Barossa Shiraz wine will spend anywhere from a few weeks to a few years ageing in either stainless steel vats or oak barrels (the winemakers choice).  The process of racking and fining continues with the wine during the ageing process.  Preservatives are added at this time, the most common preservative is sulphur dioxide, another common preservative is potassium sorbate.  Without adding preservatives wines and easily become spoiled by bacteria, regardless of how hygienic the winemaking process is.  Filtration of the wine aids in clarification and microbial stabilization of the wine.  Large particles that are visible are removed, this process can often lighten the colour of a wine.  So the filtering technique is closely monitored by the winemaker.   

The final process in producing a Barossa Shiraz is the bottling stage.  The bottles are traditional sealed with a cork, however it is becoming more popular to use a stainless steel screw cap, or a plastic ‘cork’ to seal bottles as these reduce the likelihood or cork taint to the wine.  It is once the wine is bottled and sealed, so that no oxygen can affect the wine, that a different type of ageing begins.  Some Barossa Shiraz wines can spend several years ageing in the bottle before being released.