Why Does Yeast Turn Sugar Into Wine?

Red wine is the result of the red skin of the grape remaining with the juice while it ferments

Wine is usually made from grapes, although it can also be made from other types of berries. No matter what it is made from, the natural sugars in the juices need to be converted to alcohol. If the final alcohol content is fairly low, the result is wine; higher percentages yield spirits or liquors.

Function

To make wine, grape juice needs to go through the fermentation process. Yeast has an important role in this process. After storing the juice in containers at a set temperature, the yeast starts to turn the sugar into alcohol and carbon dioxide.

Identification

Yeast is a type of fungi, though not all yeasts are the same. To make wine, the sugar fungi form is required.

Process

The enzymes in the yeast transform the sugar into carbon dioxide, which makes the drink fizzy, and ethyl alcohol, which forms the alcoholic content. Oddly enough, the alcohol formed by the yeast in the first place destroys it. This happens at different levels depending on the strain of yeast: 5 or 6 percent alcohol will begin to destroy brewer's yeast, whereas wine yeast can tolerate up to 10 percent alcohol. For this reason wine makers at home check to see whether the liquid tastes of yeast. If it still does, it's not ready to drink.

References

• Chemical Engineering Tools and Information: Wine and Wine Making
• Yo Brew: Alcoholic Fermantation By Yeast Cells