Terms & Definitions

Question 1

Sedimentation

Answer 1

A form of clarification. It is also sometimes called ‘settling’. Suspended solids in must or wine are left to fall over time with gravity.

Can occur prior or post fermentation

Question 2

Centrifugation

Answer 2

A machine that comprises a rapidly rotating container which uses centrifugal forces to separate solids from liquids

Question 3

Bentonite

Answer 3

A form of clay that adsorbs unstable proteins and unstable colloidal coloring matter.

Used in the winery as a fining agent.

Can be used to fine must as well as wine

Question 4

Main shoots

Answer 4

The primary unit of wine growth. Major structures, which are collectively called the canopy, are the buds, leaves, tendrils, lateral shoots, and inflorescence/grape bunches.

The main axis of the shoot transports water and solutes to and from the difference structures. Stores carbohydrates.

Question 5

Solutes

Answer 5

Substances that dissolve in a liquid to form a solution, ie include sugars and minerals

Question 6

Canes

Answer 6

When the leaves fall from the vine and the green shoots lignify (become woody, rigid and brown)

Occurs in the late summer

Question 7

Buds

Answer 7

The structures of the shoot that form between the leaf stalk (petiole) and the stem. They contain all the structures in miniature that will become the green parts of the vine

2 main types are compound buds and prompt buds.

Question 8

Compound buds or latent buds

Answer 8

Future season’s buds

Produce the shoots in the next growing season. Form in one growing season and break open in the next growing season.

Question 9

Prompt buds

Answer 9

Current year’s buds

Form on the primary shoot and produce lateral shoots. Form and break open in the same growing season.

Question 10

Lateral shoots

Answer 10

Secondary shoots that grow from the prompt buds. They are smaller and thinner than the primary shoots

Main function: allow the plant to carry on growing if the tip of the primary shoot has been damaged or eaten

Often produce inflorescence (ex. Pinot Noir)

Question 11

Tendrils

Answer 11

Pair of the shoot that can help provide support

Question 12

Leaves

Answer 12

The main site of photosynthesis

Question 13

Transpiration

Answer 13

The process that draws water and nutrients from the soil up through the wine to the leaves. Occurs as the water diffuses from the leaf

Stomata partially close if the vine is water stressed, which can help conserve water, but limits photosynthesis by presenting CO2 from entering the vine

Question 14

Inflorescence

Answer 14

A cluster of flower on a stem => becomes a bunch of grapes at fruit set

Usually between 1-3 on a shoot

Question 15

Grape bunches

Answer 15

Fertilized inflorescence

Tight bunches are more prune to fungal disease due to the increased likelihood of grape-skin splitting and lack of air flow throughout the bunch

Question 16

Conventional, modern winemaking

Answer 16

Builds on the scientific understanding of the processes which convert grape must into wine.
-Influenced by Louis Pasteur’s work (1860s) on identifying bacteria and yeasts

Includes

• Temperature control
• Use of additives and/or processing aids of many types
• Manipulations

Goal: produce stable wines that reliant display fruit character and have no faults

Question 17

Organic winemaking

Answer 17

Making wine with certified organically-grown grapes and complying with rules that restrict certain practices from being performing during the winemaking process

Question 18

Ecocert

Answer 18

Certification agency that issued a full list of allowable additives and processes allowed in organic winemaking

Question 19

Biodynamic winemaking

Answer 19

Made from certified bio dynamically grown grapes

Question 20

Demeter International

Answer 20

Main certifying association for biodynamic wines

Question 21

Natural winemaking

Answer 21

Reject modern interventions in favor of artisan practice: “nothing added, nothing removed”

No agreed/certified definition. Usually refers to wines made with the fewest possible manipulations (ie low-intervention winemaking)

Question 22

Natural winemaking certification organizations

Answer 22

Vin methode nature - France; first nationally recognized certification

L’Assoication does Vins Naturels - France

VinNatur - Italy

Question 23

Amphorae

Answer 23

Giant clays pots that age wine underground

Question 24

Oxidation reactions

Answer 24

The reactions caused by the presence of oxygen that create products that then go on to react with many must and wine compounds

Question 25

Thiols

Answer 25

A category of aromatic compounds that are released during fermentation that give the box tree aromas in Sauvignon Blanc (ex. 4MMP)

They break down the presence of oxygen => can lead to the loss of fruitiness

Book sites thiols as an example of an aroma precursor present in grape must that creates aromas due to the fermentation process

Question 26

Terpenes

Answer 26

A category of aromatic compounds that are released during fermentation that give fruity and floral aromas to wine. Ex’s Linalool and geraniol => grapes aromas/flavors in Muscat

Question 27

Acetic acid

Answer 27

A byproduct of fermentation that gives vinegar it’s characteristic odor

Question 28

Methoxypyrazines

Answer 28

Occur in Sauvignon Blanc that give a grassy, green pepper aroma

Book sites as examples of aromatic compounds found in grapes

Question 29

Rotundone

Answer 29

Occurs in Syrah and Gruner Veltliner that produce a pepper aroma

Book sites as an example of an aromatic compound that is found in grapes

Question 30

Esters

Answer 30

Compounds formed by the reaction of certain acids and alcohol, a majority of which are created through the action of yeasts in the fermentation process

Responsible for the fresh and fruity aromas => essential in young wines

Book sites as examples of aromas that are bo-products if the fermentation process

Question 31

Isoamyl acetate

Answer 31

And ester that gives the aroma of banana (when highly concentrated) - Ex. in Beaujolais Nouveau

Others produce flavors of apple, pineapple, etc

Question 32

Ethyl acetate

Answer 32

An ester that gives off the smell of nail polish, ie what causes volatile acidity in high quantities

Question 33

Acetaldehyde

Answer 33

An ester that occurs in wine due to the oxidation of ethanol; also called ethanal

Nutty, apple and even a stale smell (often seen as a fault); however, gives Fino sherry it’s distinctive smell

Question 34

Diacetyl

Answer 34

Produced during fermentation, esp malolactic conversion => buttery aroma

Question 35

Vanillin

Answer 35

An organic compound

Aromas of vanilla

Can be derived by aging in new oak barrels

Question 36

Eucalyptol

Answer 36

A monoterpenoid (a colorless liquid), which can be volatized from eucalyptus trees by heat and absorbed in the waxy layer of the skins of grapes in nearby vines

Question 37

Glycerol

Answer 37

Compound derived from the sugar in grapes; contributes smoothness and perception of fullness in body. Slightly sweet taste

Ex. Botrytis wines and wine made by carbonic maceration

Question 38

Phenolics

Answer 38

A group of compounds that occur in grapes, esp in the skins, stems, and seed, which include anthocyanins and tannins

Have an anti-oxidative effect

Question 39

Anthocyanins

Answer 39

Color pigments responsible for the red or blue tints in red and rose wines

Question 40

Tannins

Answer 40

Compounds that bind with proteins in the mouth, giving a drying sensation on the palate

Question 41

Ullage

Answer 41

The headspace of air between the wine and the top of the container

Question 42

Inert gases

Answer 42

Chemically inactive gases that do not react with compounds in the wine.

Ex. Nitrogen, carbon dioxide, and argon

Question 43

Sulfur dioxide

Answer 43

A preservative that is almost universally used in winemaking. 2 main properties:

1) Anti-oxidant
2) Anti-microbial

Question 44

Anti-oxidant

Answer 44

Reduces the effects of oxidation by reacting with the products of oxidation reactions => can’t oxidize further compounds

Question 45

Anti-microbial

Answer 45

Inhibits the development of microbes such as yeast and bacteria

Question 46

Bound SO2

Answer 46

Proportion of must or wine that has dissolved SO2 that has reacted with compounds in the liquid

It’s infective
Against oxidation and microbes

Question 47

Free SO2

Answer 47

Proportion that is not bound. Majority of free SO2 exists in a relatively inactive form

A small proportion exists as molecular SO2, which is the most effective against oxidation and microbes

A greater proportion of free SO2 is in the molecular form at lower pH levels