🍷 Grape sugar
Glucose and fructose in the berries; yeast turns them into alcohol.
Grape sugar is the sweet matter in the berries, mainly glucose and fructose. In ripe grapes they are present in roughly equal amounts. Sugar makes up about a fifth of the juice. Where does it come from? Leaves build it in the light through photosynthesis, and it then moves into the berries.
This sugar is what turns into wine. Yeast eats glucose and fructose and releases alcohol and carbon dioxide. The more sugar in the juice, the stronger the wine can be. Degrees Brix are used to estimate it, showing the share of sugar in the juice. As a rule, about 17 grams of sugar per litre gives about 1% alcohol.
If not all the sugar has fermented, the wine stays sweet. A dry wine has very little residual sugar. In milk the sugar is lactose, while in grapes it is glucose and fructose. Watching sugar is important when choosing the harvest date, so it is measured in the vineyard with a refractometer.
What it includes
Links
- Previous step
- 🍷 Photosynthesis
- Part of
- 🍷 Wine
- Wine and milk
- 🧪 Lactose
Frequently asked questions
What sugar is in grapes?
Mainly glucose and fructose, in roughly equal amounts.
How does sugar become alcohol?
Yeast eats it during fermentation and releases alcohol and carbon dioxide.
How is grape sugar measured?
In degrees Brix, usually with a refractometer.
Similar
🍷 Refractometer · 🍷 Oenology · 🍷 Reduction (wine) · 🍷 Methuen Treaty · 🍷 Wine routes · 🍷 Wine tourism