6.2 Winemaking Flashcards
It can be difficult to extract dense juice and flavors from Rutherglen Muscat to be used for fermentation. Why is that and what can be done to mitigate this?
When picked, Muscat grapes are partly shrivelled making it hard to extract the dense juice through pressing immediately. Crushed Muscat grapes therefore ferment briefly on their skins to break down the pulp and release sugar and flavours. Enzymes may be added to the juice and various cap management techniques (punching down, pumping over, rotary fermenters) employed to aid extraction.
Describe the fermentation and fortification process of Rutherglen Muscat.
Once the juice gains 1-2 per cent of alcohol, it is quickly drained off the skins, which are pressed and the combined juice then fortified to reach around 17.5% abv. Fortifying spirits of at least 96% abv are usually chosen; most producers aim to retain Muscat character in the wine and therefore want a spirit that is neutral. A lower strength spirit would need to be added in greater volume and would further dilute the wine.
True or false?
Rutherglen Muscats are typically not clarified or filtered.
False.
The wines are clarified by racking off lees or by light filtration. Winemakers may now make adjustments to pH and perform light fining for protein stability. The aim is to avoid deposits that might cause off-flavours during maturation.
Rutherglen Muscats are usually matured in _________________, often in warm conditions.
Rutherglen Muscats are usually matured in very old oak vessels, often in warm conditions.
The vessels consist of large round or oval casks of the capacity of 1,300 to 9,000 litres and smaller barrels of 180 to 500 L. Small vessels promote greater concentration through evaporation, more oxidation and generally a quicker maturation. The wood is often very old as the flavours and tannins from new oak are not wanted in these wines.
Describe the conditions Rutherglen Muscats are often matured in.
The wines are matured in very old oak vessels, often in warm conditions. Classically, the wines are matured in warehouses with tin roofs, which become hot in the summer. The positioning of barrels is important; those nearer the top of stacks are subjected to warmer temperatures and mature more quickly. Some producers also have sections of their warehouse facilities that are insulated to retain more-even, cooler temperatures throughout the year, which generally slows the maturation and can be used to retain greater freshness.
Describe the vinification process of Rutherglen Muscat maturation and what happens to the wine during this stage.
During maturation, water evaporates gradually from the oak vessels, causing alcohol, sugar and acidity levels to rise gradually over time. The speed of this process is impacted by the heat, the size of the vessel and also humidity, with warm, dry conditions leading to a quicker rate of evaporation. Some producers will aim to reduce ullage by topping up the barrels frequently, maintaining a fresher, less oxidative style of wine. Others will top up barrels less frequently to encourage oxidative flavours to develop.
Overall, during maturation, the wines gradually turn to from pale pink, ruby or garnet to deep brown, increase in sweetness, alcohol and acidity levels, become fuller-bodied and more syrupy, and develop more tertiary flavours.
Most Rutherglen Muscat wines are ___________ and an important aspect in the production of the wine is the blending of younger and older wines to gain the optimum balance between freshness and complexity and to retain a consistency of style year on year.
Most Rutherglen Muscat wines are non-vintage and an important aspect in the production of the wine is the blending of younger and older wines to gain the optimum balance between freshness and complexity and to retain a consistency of style year on year.
True or false?
Some Rutherglen Muscat producers use a modified solera system during maturation.
True. They do this by removing some wine from barrel and replacing it with younger wine, although often not in quite the same systematic way used in Sherry solera systems.
True or false?
Blending a wine does not contribute to a winery’s ‘house style.’
False.
Blending helps producers achieve their ‘house style’. For example, blending in a high percentage of wines that were made from less-ripe grapes (note, not under ripe), have been stored in cooler conditions or that have been matured for less time can help create a fresher, fruitier style. Blending wines that have been purposely made with different levels of residual sugar can fine-tune the perception of sweetness in the final wine.
