Wine Chemistry & Faults

Question 1

List the 5 major components of wine.

Answer 1

Water, alcohol, sugar, acid, phenolic compounds

Question 2

Other compounds that are found in wine what have been aged or sur lie (found in very small amounts) are

Answer 2

Yeast and proteins

Question 3

Water makes up _____% volume of wine.

Answer 3

80%-90%

Question 4

Alcohol makes up ____% volume of wine.

Answer 4

10 - 15%

Question 5

What is the primary alcohol found in wine?

Answer 5

Ethyl alcohol

Question 6

What 3 other types of alcohol are found in wine?

Answer 6

Glycerol, methanol and fusel

Question 7

Acid give wine much of it’s

Answer 7

Structure, balance & thirst quenching qualities

Question 8

Acids make up ____% volume of wine

Answer 8

.5 -.75%

Question 9

What are the 6 principal acids found in wine?

Answer 9

Tartaric, malic, citric, lactic, succinic, acetic

Question 10

What is the most prevalent acid found in wine?

Answer 10

Tartaric

Question 11

What acid is the strongest in terms of pH?

Answer 11

Tartaric

Question 12

The sharp tasting acid frequently associated with green apples is

Answer 12

Malic

Question 13

Under ripe and cool climate grapes are typically high in ____ acid.

Answer 13

Malic

Question 14

Which acid exists in such minute amounts that special equipment is required to measure it?

Answer 14

Citric

Question 15

Lactic acid is created in wine by lactic acid bacteria. T or F

Answer 15

True

Question 16

The acid found in most types of vinegar is

Answer 16

Acetic

Question 17

Acetic acid is volatile. T or F

Answer 17

True

Question 18

Acetobactor is the result of a chemical reaction between oxygen &

Answer 18

Ethanol

Question 19

What acid has a sharply bitter and salty taste?

Answer 19

Succinic

Question 20

What are the grape acids?

Answer 20

Tartaric,
malic
citric
Succcinic (in ___and in fermentation)

Question 21

What are the grape fermentation acids?

Answer 21

Lactic,
acetic
succinic (in both grapes and in ___)

Question 22

Total Acidity (TA) refers to

Answer 22

the volume of all acids in the wine.

Question 23

The pH level of a wine represents

Answer 23

the combined chemical strength of the acids present.

Question 24

The combined chemical strength of the acids present in wine is measured by

Answer 24

The pH level

Question 25

The volume of all acids present in wine is measured by

Answer 25

The Total Acidity (TA)

Question 26

Grapes contain ___% to ___% of sugar at harvest

Answer 26

15% - 28%

Question 27

Grapes contain roughly equal amounts of what two sugars?

Answer 27

Fructose and glucose

Question 28

List the 5 phenolic coumpounts found in wine?

Answer 28

Anthocyanins, flavanols, vanillin, tannin, resveratrol

Question 29

Which phen compound gives red wine it's color?

Answer 29

anthocyanins

Question 30

Which phen compound gives white wine it's color?

Answer 30

Flavanol

Question 31

The phen compound that gives big red wines "backbone" is

Answer 31

Tannin

Question 32

Which phen compound is a natural preservative?

Answer 32

Tannin

Question 33

Which aromatic phen compound is found in oak?

Answer 33

Vanillin

Question 34

The phenolics of a grape are concentrated primarlily in its _____ and ______.

Answer 34

Skin and seeds

Question 35

When some phen compounds combine into longer molecule chains it's called

Answer 35

Polymerization

Question 36

List 4 other minor compounds of wine.

Answer 36

Aldehydes, esters, sulfites, dissolved gasses.

Question 37

Oxidized alchohols that are formed when wine is exposed to air are called

Answer 37

Aldehydes

Question 38

The most common aldehyde found in wine is

Answer 38

acetaldehyde

Question 39

Esters are molecules that result in the joining of a _____ and _______.

Answer 39

Acid & alcohol

Question 40

The most common ester found in wine is

Answer 40

ethyl acetate

Question 41

Ethyl acetate is the ester of _______ and ______.

Answer 41

Ethanol and acetic acid | imparts a fruity, flowers aroma

Question 42

In high concentrations ethyl acetate imparts faulty aromas of

Answer 42

nail polish remover, varnish, glue

Question 43

What dissolved gas is routinely found in wine?

Answer 43

Carbon dioxide

Question 44

"Contains Sulfites" must be on US labels that contain more than ______ of sulfur dioxide.

Answer 44

10ppm

Question 45

Wines with a musty, moldy, dank basement, wet cardboard aroma are often found to have what fault.

Answer 45

2,4,6 TCA or cork taint

Question 46

Another term for TCA is

Answer 46

cork taint

Question 47

TCA is a mold. T or F

Answer 47

True

Question 48

Most people can detect TCA at concentrations of ____ to ____ parts per ______.

Answer 48

2 to 7 parts per trillion

Question 49

Wines with the off odor of burning matches is a result of high concentration of

Answer 49

Sulfur dioxide

Question 50

Hydrogen sulfide (H2S) gives off the odor of

Answer 50

Rotten eggs

Question 51

The odor associated with wine that's sat too long in a barrel or sur lie and absence of oxygen is

Answer 51

Rotten eggs, Hydrogen sulfide

Question 52

Mercaptan is the result of the combination of sulfur and

Answer 52

ethyl mercptan | may form as a combination of sulfer and ethanol

Question 53

ethyl mercptan smells like

Answer 53

garlic and onions

Question 54

What 2 bacterias can live in wine?

Answer 54

Acetobactor and lactic bacteria

Question 55

The odor of vinegar is _________ acid.

Answer 55

Acetic

Question 56

The odor of rancid butter or spoiled cheeses is ____ acid.

Answer 56

Butyric

Question 57

The odor of sauerkraut or goat is _______ acid.

Answer 57

Lactic

Question 58

The odor of nail polish remover is ______ acid.

Answer 58

Ethyl acetate

Question 59

The odor of crushed geranium leaves is normally caused by

Answer 59

an incomplete malolactic fermentation

Question 60

The odor of band aid, medicinal, horsey or sweat is called

Answer 60

Brett

Question 61

Brett is a yeast. T or F

Answer 61

True

Question 62

Odors occurring in conditions that lack oxygen are termed

Answer 62

Reductive