How is wine made?
So you want to know how wine is made? It’s really a very simple process…
In basic terms, grapes are crushed to get the juices out, this juice is clear and left with the skins of the red grapes to make red wine. Contrary to popular belief, red grapes do not give red grape juice. It is contact with the skins, which contain red pigment, that produce the red color.
Once the juice has been extracted, either in the traditional manner of crushing under foot or under the pressure of a commercial press, the juices are then gathered in a fermenter and a yeast is added. This is not your usual bread yeast, as that cannot cope with the high alcohol levels. Instead a special yeast for wine making is added, and this basically eats the sucrose (sugar) in the grape juice and turns it into alcohol and gives of carbon dioxide.
The sugar content of grape juice can vary wildly from anywhere between 16-23 Brix, so most modern manufacturers will add more sugar (if needed), to produce higher alcohol content (ABV – Alcohol By Volume). Brix is a measurement of sugar content, around 24 Brix will give around 13% ABV, this can be measured with a refractometer.
After a period of days to weeks, depending on how much sugar needs to be fermented, all the sugar will have been turned in to alcohol. At this point we then have a decision…
Will the wine be aged? Most red wines, some white wines, and most sparkling wines are aged. Red and white wines will be aged in oak barrels, although other woods have been known to be used. Wood selection and the treatment of the barrel plays a big part in the flavor of the wine. Oak barrels generally come in a: Light, Medium, Medium Plus or Heavy toast. This is where the cooper (barrel maker) toasts or chars the inside of the barrel. Specialist coopers also have the ability to toast the barrels in different ways, meaning you can get even more intricate with the taste they impart. The age or uses a barrel has had, also impart a particular taste and aroma.
For sparkling wine, the wine will be aged and bottled for a secondary fermentation (with the addition of a small amount of sugar) in bottles, which are held in racks. Every day each bottle is given a twist, a white mark as the picture above shows is used to note where the bottle is in the process… This is done so that any sediment settles in the bottle is driven down the neck of the bottle and towards the cap. That’s right, when making sparkling wine, we use crown caps on the bottles with the corks being added later, purely for effect as we could quite easily use crown caps (beer bottle style caps).
The use of crown caps does help make a process called de-gorging easier though. Remember I mentioned the sediment from the secondary (bottle) fermentation of sparkling wine? That is removed by holding the bottle upside down, freezing the neck of the bottle, and removing the cap and a small amount of the ice from the top (or bottom with it being upside down) of the bottle neck. This is where the sediment has been collected thanks to the twist a day.
So, there you have it, a very brief run down on how wine is made. Hope you found it interesting!