Handcrafted for Generations - Fortified winemaking 101

Handcrafted for Generations - Fortified winemaking 101

At Stanton & Killeen, we specialise in crafting both barrel-aged and bottle-aged, fortified wines. How the fortified wine is made will determine how long you can cellar the wine and how quickly you need to drink it once opened.

Wines aged in small and large oak casks - such as Muscat, Topaque and Tawny – get their unique flavour profile and lusciousness from the time spent in barrel and the process of oxidation. The longer they spend in the barrel, the more they develop. At S&K, we do all the hard work for you by having a modified solera system where we mature and bottle wine according to similar style and age. We bottle according to the Rutherglen classification system with Rutherglen, Classic, Grand and Rare, indicating a graduating system of richness, complexity and age.

These wines will not continue to mature in the bottle. We bottle them in small amounts to keep them fresh and recommend opening them within two years of purchase. Keeping a Grand Muscat in your cellar for ten years will only reduce the bright, fresh flavours of the wine. Once opened, you have a bit of time to consume the bottle as it will not 'go off'. Our barrel-aged fortified wines are freshest within the first few weeks upon opening, and it is our recommended drinking timeframe; however, a Muscat left open for several months will still be okay. They have already oxidised; therefore, there's no risk of the wine tasting like vinegar within a few days.

On the other hand, you may have heard about Vintage Ports (we call ours Vintage Fortified) that can last for many years in the cellar. There's something quite special about opening a 30-year-old wine from your birth year. They can last that long due to different winemaking methods and because they are usually bottled within a year or two of production. Due to this, a bottle-aged Vintage Port/Fortified needs to be enjoyed within a few days of opening before they oxidise the same way a table wine does.

So how exactly are these wines made? In the world of winemaking, the production of table wine and fortified wine share certain similarities. However, applying unique winemaking techniques sets fortified wine apart, allowing for the creation of distinct flavour profiles synonymous with fortified wines.

CRAFTING A BARREL-AGED WINE (MUSCAT, TOPAQUE OR TAWNY)

Step 1: Grape Selection

Our winemaker will select the grape varieties best suited for the fortified wine. For Muscat we use Muscat à Petits Grains Rouge; for Topaque, we use Muscadelle; and for our Tawny wines, we use a combination of our red grape varieties. 

 Step 2: Harvesting at the perfect time.

Much of the wine's flavour, intensity and character comes from the vineyard. Rutherglen is famous for it's perfect combination of a continental climate, moisture-holding soil and long ripening periods (among other aspects) that make it the ideal location for growing fortified wine varieties, particularly Muscat. The winemaker will patiently wait until the grapes are at optimal ripeness and flavour before harvesting them: 17 and 18 Baumé for Muscat and Topaque, and Tawny is around the 14 Baumé mark.

Step 3: Fermentation.

After harvesting, the grapes are fermented on skins for a short period, creating 1-2% alcohol before the addition of fortifying spirit stops fermentation after pressing. In contrast, dry table wine is usually picked at 12-13 Baumé and is fermented until that level drops to around 0.2, signalling that all sugar has now converted into alcohol. Whereas with barrel-aged, fortified wines, we want to keep the sugar high and raise the alcohol level by adding a fortifying spirit, usually a neutral grape spirit.

Step 4: Pressing & Fortification.

After a quick fermentation, the juice is pressed to separate it from the skins, allowing for the extraction of desired flavours. After pressing, the wine is immediately fortified. To fortify the wine, the winemaker adds a neutral grape spirit, which increases the alcohol content and stops fermentation completely. This step halts any further sugar conversion, resulting in the characteristic sweetness of Rutherglen fortified wines.

Step 5: Barrel Aging

Following fermentation, the fortified wine is transferred to mature oak casks of various sizes; many Stanton & Killeen fortified casks are 100+ years old. Mature oak allows the flavours of fortified wine to integrate and develop but without the overt influence of new oak. Our aged casks and barrels are merely vessels that provide the medium for slow and gentle maturation. In other words, it is the flavour of the fruit, not oak, that is of the highest importance when creating our fortified wines. The ratio of big and small casks depends on our winemaker's blending program—the smaller the cask, the quicker the concentration and development of the wine. Cask sizes can vary from 60 to 50,000 litres. The largest cask we have at Stanton & .Killeen is 5000 litres.

Interestingly, the placement of casks or barrels can influence the development of the fortified wine, with wine from barrels in warmer areas of the winery maturing faster than those kept in colder areas. Similarly, wine development accelerates over summer and slows down during winter. Evaporation also plays an integral part in the maturation of fortified wine. On average, the maturing casks lose 3-5% of their volume per year to the 'angels'. Over 20 years, the angels get half of every barrel. The evaporation makes the production of these wines a costly enterprise, but without this process, our fortified wines, particularly our Muscat would not have its title of 'world's richest wine.'

Step 6: The Blending.

Contrary to popular belief, age is only one factor in determining the complexity of a fortified wine. At Stanton & Killeen, we create our final fortified blends using a modified solera system - a blending and ageing process that ensures consistency of style.

When blending a fortified wine - let's say it's our famous Classic Muscat - we're looking to stay true to our S&K house style, meaning our Classic Muscat will taste the same every time, even if it is decades between cellar door visits. We're also looking to keep the Muscat blend at an average of 12 years barrel-aged. When we say average age, that doesn't mean that every ml of Muscat used in the blend is 12 years old; more that the average age of all Muscat used in the blend equates to an average age of 12 years. We use different vintages of all ages, and each brings something unique to the blend. Young Muscat brings freshness, fruit and florals, and older Muscat brings complexity, acidity and depth - you need a perfect balance of both depending on which tier of Muscat you are creating. 

Step 7: Clarify & Bottle.

After blending the winemaking team will clarify the fortified wine to remove sediment or impurities. This can be done through various methods, such as racking or filtration. Once clarified, the wine is transferred into a stainless steel tank where it is kept until it is bottled. Our fortified wines are hand-bottled on demand to ensure optimal freshness and flavour in every bottle. The bottles are then labelled and ready for purchase.

CRAFTING A VINTAGE FORTIFIED (BOTTLE-AGED WINE)

Step 1: Selecting the best varieties.

Our winemaker will begin by carefully selecting the grape varieties best suited for our Vintage Fortified. At Stanton & Killeen, this is usually a blend of the best quality fruit from the following Iberian varieties: Tinta Roriz, Touriga Nacional, Tinto Cao, Tinta Barroca and Souzão. We also may add Shiraz, Durif and Grand Noir as they blend and complement our Portuguese varieties well.

Step 2: Harvesting at the perfect time.

So much of the wine's flavour, intensity and character comes from the vineyard. The Winemaker will patiently wait until the grapes are at optimal ripeness and flavour before harvesting them, this is usually 13-14 Baumé for our Vintage Fortified varieties.

Step 3: Fermentation & Fortification.

After harvesting, the grapes are fermented on skins for a short period until the sugar levels ferment to 5 Baumé (residual 3 Baumé, which is significantly lower than the residual Baume when making our barrel-aged, fortified wine). Once the correct levels are attained, the wine is fortified on skins and pressed within 6-12 hours. At this point in time, each of the varieties is kept separate and made into single variety, single vintage fortified wines, we call these 'parcels' of wine, which will be used later in the final blending process. When fortifying each of the varieties the winemaker must consider the variety and desired flavour profile before choosing which fortifying spirit to use. Generally, all Portuguese varieties are fortified with a neutral spirit as they are delicate and soft. The more robust varieties such as Shiraz or Durif can handle a bigger spirit flavour so we will often use a light brandy spirit for fortifying these. 

 Step 4: Barrel Aging.

We will age the Vintage Fortified varieties in old oak barrels to allow the flavours to develop and integrate. The duration of aging can vary; however, at Stanton & Killeen, we often age our Vintage Fortified in the Portuguese way, which is to age until the second spring after the Vintage. 

Step 5: Selecting & Blending.

Once the second spring rolls around, the winemaker must create the final bottled blend. Each Vintage Fortified wine parcels is tasted to decide which will make the cut. Only the best-quality wine parcels will make it to the final blend. The Vintage, fruit quality, and desired style will dictate what ratio of these varieties will make up the final blend. We must create a blend that will hold its fruit and tannins for decades, as this is typically how long people will hold on to these wines before drinking. 

 Step 5: Clarify and Bottle. 

Once the final blend has been created, the winemaking team will clarify the wine to remove sediment or impurities. This can be done through various methods, such as racking or filtration. Once clarified, the wine is transferred into sterilised bottles and is corked or capped depending on the size (375ml, 750ml or Magnum). The bottles are then labelled and stored until they are ready for release to our customers. 

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