The transformation of whey into a premium spirit sounds like magic. But in pioneer distilleries in Australia, it is a reality. It not only replaces a sustainable option for a grain or potato based spirit, it also shows the amazing innovative fermentation and distillation. The following is a description of the transformative science that goes into making award-winning booze from the cheese making milky residue.

The core challenge and opportunity whey presents is in the composition of the 'sugar' whey.

Whey is the liquid that separates during the cheese making process. It makes up the majority of the composition of whey. However, there valuable proteins and a sugar called lactose in the whey composition.

The issue is that the common distilling yeasts that are used for grain or potato are not efficient in sugar consumption. Without the right yeast, the sugar needed to make alcohol remains locked in the whey. The distilleries get around this by using specific strains of dairy yeast or providing an external enzyme called lactase. This enzyme breaks the complex lactose in simple sugars like glucose and galactose. This is the first critical step in unlocking the alcohol potential for whey.

The Fermentation: Brewing the "Milk Beer"

Once the lactose is transformed into simple sugars, sweet liquids undergo the process of conversion into an alcoholic wash. This is now the sweet alcoholic wash stage.

The Gentle Conversion

In large fermentation tanks, the prepared whey is mixed with the specialized yeast. The yeast then consumes the simple sugars and subsequently produces alcohol (ethanol) and CO2.

Speed and Temperature

This fermentation process is slower than grain fermentation. Precise temperature control has to be performed because if the whey compounds are to be off balanced, off-flavours will emerge and negatively impact the alcohol quality.

Low ABV Wash

The liquid, "milk beer" or "whey wine" and the wash are all much lower in alcohol by volume (ABV) compared to a grain wash. The wash is ready for distillation at this point.

Crafting Distilled Spirits in Australia 

Australian craft distillers utilize copper pot stills. Copper is necessary because it removes the sulphur compounds produced in fermentation. This ensures that the end product is unblemished and smooth and that the spirit is clean. 

The Cuts in Fractionation 

The distiller heats the wash until the alcohol vapourizes. As the spirit comes off the still, it is divided into three parts or fractions. 

Heads (Foreshots) 

This is the initial and most volatile portion, and it is thrown away. 

Hearts 

This is the purest and highest quality middle part. This is the award-winning vodka. 

Tails (Feints) 

The last part is, once again, less pure, competing with the last portion that is recycled into the next wash. 

Whey as the Base Spirit 

Whey washes tend to be the "cleaner" base spirit in comparison to some others. This means that while there still are multiple distillations, the initial wash less needless impurities, which distillate works out to be smoother. 

Why Score the Vodka is So Smooth 

Whey vodka derives its smooth texture from the spirit's source. The soft, unfermentable, and milk minerals components that pass through the distillation add to the creamy, soft mouth feel and contrasts the sharper finish of most grain vodkas.

The Last Step: Water, Time, and Proofing

In this step we prepare the high proof spirit for bottling.

We Proof it Down: The spirit abs reduction to a lower called bottling strength which is 40% abv. The type of water we use when cutting the spirit is extremely important. Water source will contribute to the texture and taste of the vodka.

We ensure Minimal Filtration: Most of the time the whey base and the precise distillation is more than enough to create a pure spirit. They will then n opt for minimal or no extended filtration. This is to maintain the soft character of the spirit and to allow and showcase the natural silkiness.

By tackling the lactose challenge coupled with the science of the copper still, Australian distilleries have not only created a new spirit but also developed a new and sophisticated category of sustainable vodka. This is a fine example of a distillers artistic and technical skill.