Wine Aromatics

Question 1

Give 2 examples of aromas that come from the grapes.

Answer 1

Methoxypyrazines- grassy, green pepper aromas- eg from Savy B
Rotundone- pepper aroma in GV and Syrah

Question 2

What are aroma pre-cursors?

Answer 2

Compounds that are not aromatic until they go through fermentation

Question 3

Give 2 examples of aroma precursors.

Answer 3

Thiols- eg 4MMP- give box tree aromas in Savy B
Terpenes- fruity, floral aromas- eg Linalool and geraniol= grapey aroma in Muscat

Question 4

What are Esters?

Answer 4

-compounds formed by reaction of certain acids and alcohols
-majority created through actions of yeast in ferm.Wha

Question 5

What aromas to Esters contriubte?

Answer 5

-fresh and fruity- essential for young fruity whites
-most common= isoamyl acetate= banana
- also- Ethl acetate (nail varnish remover smell)

Question 6

What are the 4 aromas that are created from ferm and it’s by products?

Answer 6

-Esters
-Acetaldehyde
-Diacetyl
-Yeast

Question 7

How does Acetaldehyde occur?

Answer 7

Through oxidation of ethanol (ethanal)

Question 8

What aromas does Acetaldehyde contribute?

Answer 8

-masks fruity aromas and has stale smell (fault)
- important in sherry

Question 9

How is diacetyl produced?

Answer 9

Through ferm and mlf
- butter aroma

Question 10

What flavours can yeast contriubte?

Answer 10

-reductive sulfur compounds during firm and lees ageing
-struck match good
-rotten eggs- bad

Question 11

Give 2 examples of aromas that occur from other sources

Answer 11

Vanillin- oak
Eucalyptol- eucalyptus trees by heat and absorbed in waxy layer of skins of grapes in nearby vines