This is a mix of technical information, glossary of terms used in our notes, winemaking photos and videos.
They are imported from France ready to use. They hold 225 litres which is equivalent to 300 bottles of wine. Barrels from different coopers (barrel makers) have different characteristics depending on where the wood was sourced from, how it was dried and how it was handled and toasted during the barrel making process etc – we purchase from different coopers depending on the impact we want the barrel to have on the wine. We have recently started using some barrels from a French cooper who is sourcing oak grown in Hungary as Tony likes the characteristics this imparts to selected wines.
Barrels contribute useful oak for 4 – 5 years, albeit in diminishing quantities. After that, a barrel can be used for ageing wines prior to bottling for a few more years. Then we pull them apart and they start a new life as furniture or fencing!
Used for white wines . Whole bunches of grapes (stems and all) are put into the press.
Used for red wines where the grape bunches are put through a machine that removes the stems and gently breaks the berries. The broken fruit is then pumped to open fermenters for fermentation – refer red winemaking process overview.
After fermentation, there is a very high concentration of yeast cells present in the wine – approximately 200 million yeast cells per ml wine. As the fermentation finishes, the yeast run out of nutrients, there is no longer any sugar left for them to metabolise and they ‘poison’ themselves with alcohol – they die. When they die, the membrane surrounding the yeast cell ruptures and the yeast contents are released into the wine – this is called ‘autolysis’. The key components released are long-chain sugar-like molecules called polysaccharides. These tend to have a ‘wrapping’ effect around many of the coarse elements in the wine, thereby softening and improving the texture and mouthfeel.
In addition, the yeast impart a (Champagne-like) ‘bready’ or ‘mealy’ character to the aroma and flavour – providing additional layers of flavour and enhancing complexity of the wine.
A further benefit is that dead yeast suck up most of the oxygen that gets into the barrel either through the bung seal or pores of the oak staves. This helps to protect the wine from oxidation during this sensitive ageing stage.
What happens here is we encourage oxidation of unwanted phenolics at the juice stage. We achieve this by delaying the addition of Sulphur Dioxide and allowing significant contact of the juice with air for an extended period. This causes the juice to temporarily turn brown as the phenolics become oxidised (same thing as when a cut apple turns brown). The oxidised (brown) phenolics then precipitate out of the juice, forming a brown sludge on the bottom of the tank. We then rack the good juice to barrels, leaving this phenolic-laden sludge behind. Essentially we have removed the unwanted fraction prior to fermentation. Now when the wine ages in the bottle, the chemicals that would otherwise have induced premature ageing, are no longer present.
Ageing is therefore slower and more graceful. The aroma and flavour changes associated with this type of ageing are much more desirable.
A further important benefit of this technique is an improved mouthfeel. Phenolics are associated with harshness in the palate and reducing the length of the wine. Wines made using hyperoxidation are usually softer, more ‘linear’ and have a longer and more refined finish.
This technique does not work for all varieties – for example, it would kill a Sauvignon Blanc. Great for Chardonnay though.
These are the yeast that are naturally present on the grape skins in the vineyard. There is quite a trend toward use of wild yeast these days – especially in Chardonnay. There are strong indications that wild yeast impart additional complexity and certainly assist the texture and mouthfeel – the exact reasons for this are not clearly understood. Plus, winemakers seem to love to write about using wild yeast on their back labels and tasting notes – it sounds sexy.
Results can be unpredictable – they are often notoriously poor fermenters and only dominate the fermentation in the early stages when alcohol is moderately low. Wild yeast can slow down and ‘stick’ in the latter stages of fermentation, so we always have a very strong ‘rescue’ yeast on hand to finish the ferment through to dryness if necessary.
The commonly used red winemaking technique of micro-oxygenation was originally developed in the Madiran region specifically to tame the huge tannins of this variety.
Essentially it is a technique designed to emulate the continuous absorption of minute amounts of oxygen through the pores of new oak barrels. The technique involves the introduction of a highly controlled dose of oxygen into the wine to mimic this barrel effect.
How does it work? – Tannins, when newly extracted from skins and seeds are very harsh and aggressive (mouth puckering), and also very reactive with each other and with colour molecules (anthocyanins). The presence of oxygen forms a bridge between the small tannin molecules allowing them to grow sequentially to form larger tannin polymers. Over time, the size and shape of these polymers change to a softer, richer, less drying form – this is what winemakers call “melting the tannins”.
- the first step is ‘riddling’ the yeast lees down into the next of the bottle. This involves turning the bottles upside down and with gentle movements, move the lees off the bottom of the bottle so they can fall and resettle in the neck of the upturned bottle.
- removing the yeast lees from the neck of the bottle is next. We could use a neck freezer to freeze the plug of wine, containing the lees, in the bottle neck before removing the crown seal and letting the frozen wine pop out of the bottle. But, having learnt about the technique ‘à la volée’ where the crown seal is removed from the bottle without freezing the neck (and having practised this technique as we ‘tracked’ the progress of the riddling process), Tony decided this was the way to go. Once the crown seal is removed and the neck wine is disgorged, the neck is plugged (by thumb) and the pressure is allowed to release without the loss of a lot of wine.
- the next step is to replace the wine that was lost – at this point sugar can be added if a sweeter wine is required. We have chosen to keep the wine ‘dry’ (‘zero dosage’) so our topping wine was just more of the same (minus the yeast lees)
- the cork is then applied – champagne corks start life as a straight cork (like you (used to) find in any bottle of wine) but of a larger diameter, and the corking machine squeezes the lower part of the cork before pushing it part-way into the bottle
- the muselet (wire) is then applied to hold the cork in – our machine grabs hold of the loop in the wire, compresses the top over the cork and gives it a damn good twist to tighten the wire around the neck of the bottle
- a final dip in water to rinse any spilt wine off the outside, a quick dry and the job is done
- Watch our videos to see the bottles being riddled and disgorged