Wine science: From grape to bottle, how is wine made?
Mass-market wine-making, also known as viniculture, comprises several major steps.
First, after harvesting, grapes are squashed by a crushing unit, which either maintains or removes the stem and skin depending on the type of wine that is being produced.
Once crushed, the grapes are deposited into a fermentation unit, where primary alcoholic fermentation takes place. Yeast is already present in the grapes to initiate this process, but due to natural yeast generating unpredictable results, cultured yeasts are added too.
Next, the fermentation units undertake temperature-controlled stabilisation, dropping the mixture close to zero degrees Celsius (32 degrees Fahrenheit) to reduce and separate the buildup
of tartrate crystals (sediment).
At this point, the wine mix is sent for secondary malolactic fermentation, a process that takes between three and six months. Here proteins within the liquid are broken down and any remaining yeast cells and fine particles dissipate. Finally, preservatives are added to the wine, while blending and ‘fining’ are done pre-bottling.
Discover more amazing science in the latest copy of How It Works. It’s available from all good retailers, or you can order it online from the ImagineShop. If you have a tablet or smartphone, you can also download the digital version onto your iOS or Android device. To make sure you never miss an issue of How It Works magazine, make sure you subscribe today!