Wine Composition & Chemistry

Question 1

The most prevalent of the acids found in grapes and wine

Answer 1

Tartaric Acid

Question 2

The component that makes up 80-90% of the volume of most wines

Answer 2

Water

Question 3

Slow-moving “tears” that may appear in a wine glass after the wine is swirled

Answer 3

Legs

Question 4

Acid that has little or no sensory impact on the majority of quality wines

Answer 4

Citric Acid

Question 5

The continent that makes up 10-15% of the volume most wines

Answer 5

Ethyl Alcohol

Question 6

Glycerol is:

Answer 6

A type of secondary alcohol

Question 7

A sharp-tasting acid often associated with green apples

Answer 7

Malic Acid

Question 8

An acid produced via the conversion of malic acid

Answer 8

Lactic Acid

Question 9

An acid with a slightly bitter, slightly salty flavor

Answer 9

Succenic Acid

Question 10

The acid found in most types of vinegar

Answer 10

Acetic Acid

Question 11

Of the six main acids found in wine, list those that are typically found in unfermented grapes

Answer 11

Tartaric
Malic
(Citric)
(Succenic)

Question 12

Of the acids typically found in grapes, which are found in very small quantities?

Answer 12

Citric & Succenic

Question 13

Which acid is known to cause deposits known as wine diamonds?

Answer 13

Tartaric Acid

Question 14

What the name of the winemaking process that, in addition to changing a wine’s acid components, often provides wines with a creamy texture and a buttery aroma?

Answer 14

Malolactic Fermentation

Question 15

What measurement is used to define the volume of all acids present a wine?

Answer 15

Total Acidity (TA)

Question 16

What does pH measure?

Answer 16

The combined chemical strength of all the acids present in a wine

Question 17

What is a typical pH of a highly acidic wine?

Answer 17

2.9

Question 18

What pH measurement would you expect to find in a low-acid wine?

Answer 18

3.9

Question 19

What are the two main fermentable sugars found wine grapes?

Answer 19

Glucose & Fructose

Question 20

What term is used to describe a wine that does not contain any detectable sugar?

Answer 20

Dry

Question 21

Yellow pigments found in white wine

Answer 21

Flavonols

Question 22

An aromatic compound found in oak barrels

Answer 22

Vanillin

Question 23

A compound found in wine believed to be beneficial to human health

Answer 23

Resveratrol

Question 24

One of the most common esters found in wine

Answer 24

Ethyl Acetate

Question 25

The specific component that gives fino Sherries their distinctive aroma

Answer 25

Acetaldehyde

Question 26

The compounds that give red wine its red, blue, or purple hues

Answer 26

Anthocyanins

Question 27

Bitter compounds found in the skins, seeds, and stems of grapes

Answer 27

Tannins

Question 28

Molecules that result from the joining of an acid and an alcohol

Answer 28

Esters

Question 29

Matter sometimes formed as a result of polymerization

Answer 29

Sediment

Question 30

A preservative widely used in winemaking

Answer 30

Sulfur

Question 31

Oxidized alcohols formed when a wine is exposed to air

Answer 31

Aldehydes

Question 32

Molecule that promotes the release of the wine’s aromatic compounds

Answer 32

Carbon Dioxide

Question 33

T / F
Red wines that are highly acidic tend to appear more blue color, whereas low-acid red wines appear more red

Answer 33

False

Question 34

T / F
Tannins can create a textural, drying sensation on the palate

Answer 34

True

Question 35

T / F
Madeira is an example of a wine that is produced in such a way that oxidation is encouraged and expected

Answer 35

True

Question 36

T / F
Flavonols increase in white grapes with increased exposure to sunlight

Answer 36

True

Question 37

T / F
The aromatic compound vanillin, found in vanilla beans, is not found anywhere else in nature

Answer 37

False

Question 38

T / F
The phenolic compounds of a grape are concentrated primarily in its skin and seeds

Answer 38

True

Question 39

T / F
Wines may become oxidized after being exposed to heat

Answer 39

True

Question 40

T / F
It is common for winemakers to encourage the oxidation of white wines such as Chenin Blanc and Riesling by maximizing air exposure during the preliminary stages of fermentation and aging

Answer 40

False

Question 41

T / F
Ethyl acetate imparts an aroma similar to nail polish remover or glue at very low levels, whereas at higher concentrations it tends to smell of dried rose petals or perfume

Answer 41

False

Question 42

T / F
Esters represent the largest group of odiferous compounds found in wine

Answer 42

True

Question 43

T / F
Wines with greater than 2 ppm of sulfur dioxide are required to display the “Contains Sulfites” warning on the label

Answer 43

False

Question 44

T / F
Normal fermentation does not produce enough carbon dioxide to make a difference in the flavor profile of a typical table wine

Answer 44

False

Question 45

The most prevalent type of acid found in both vinifera grapes and wine

Answer 45

Tartaric Acid

Question 46

Phenolic compound responsible for the bitter taste and drying textural sensation found in many red wines

Answer 46

Tannin

Question 47

A type of molecule that results from the joining of an acid and an alcohol

Answer 47

Esters

Question 48

The typical pH range of table wines is

Answer 48

2.9 - 3.9

Question 49

A small particle created by via the crystallization of tartaric acid

Answer 49

Wine diamond

Question 50

A secondary alcohol produced during fermentation

Answer 50

Methyl alcohol

Question 51

In the United States, wine with more than 10 ppm of this compound must have a warning label

Answer 51

Sulfites

Question 52

Gives red wines their hues

Answer 52

Anthocyanin

Question 53

Which acid, created in small amounts during typical fermentation, is found in many types of vinegar

Answer 53

Acetic Acid

Question 54

Compound that could cause a wine to have slow, thick tears

Answer 54

Alcohol