Vinification

Question 1

When does vinification begin?

Answer 1

As soon as the grapes come into the winery after being harvested.

Question 2

What are some decisions a winemaker has to make BEFORE fermentation even starts?

Answer 2

• When to pick/ripeness of the grapes
• How rigorous sorting must be
• Whether or not to destem

Question 3

What are some of the vessels used for primary fermentation?

Answer 3

• Stainless steel
• Cement
• Barrels (new/used of varying sizes)

Question 4

What are some of the effects fermentation vessels can have on a wine?

Answer 4

• Aroma
• Flavor
• Texture

Question 5

Define foudre.

Answer 5

A large wooden barrel that holds 1000+ liters.

Question 6

Define barrique.

Answer 6

A smaller wooden barrel that holds 225 liters.

Question 7

What exactly is fermentation?

Answer 7

A chemical, exothermic reaction where the grapes’ natural sugars are eaten by yeasts, which are either naturally present or added by the winemaker.

When yeasts eat sugar, the main byproducts kicked off are CO2 and alcohol. Flavors and aromas are also produced.

As grape juice ferments, it becomes drier (less sweet, because the yeasts are eating the sugar) and alcoholic.

This first fermentation is also known as primary fermentation and alcoholic fermentation.

Question 8

Finish this equation:

Grape sugar + Yeast = _____

Answer 8

CO2
Alcohol
Heat
Flavors + aromas

Question 9

What is the purpose of sorting grapes?

Answer 9

To remove:

excess leaves
damaged fruit (split, raisinated, underripe, sunburned, etc.)
MOGS (Materials Other than GrapeS, including rocks, moths, insects, twigs, etc.)

Question 10

What is destemming?

Why do winemakers sometimes keep stems when making wine?

Answer 10

When berries are separated from their stems.

Stems are kept to add flavor and modify the style of wine.

Fun Fact: when a wine is vinified with stems the wine will typically be more tannic, but too many stems and the wine can taste stalky.

Question 11

What is ‘crushing’?

Answer 11

Grapes are almost always ‘crushed’ when they’re de-stemmed. Crushing releases the grapes’ juices, and it’s at this point that fermentation begins.

Note: if grapes are crushed too aggressively, the winemaker risks releasing unwanted tannins from the seeds and skins into the juice, making the resulting wine more astringent. Crushing should always be gentle.

Question 12

What are some advantages of fermenting wine in oak barrels?

Answer 12

1. Barrels add woody and toasty flavors straight into the wine;
2. Barrels encourage flavor development due to the presence of oxygen;
3. Barrels lend textural changes, softening tannins;
4. Barrels can change the color of wine via oxidation, darkening white wines and lightening red wines.