Unit 2 - Week 3

Question 1

What is plasmopara viticola

Answer 1

downy mildew

Question 2

Vitis vinifera sativa

Answer 2

functional hermaphrodite flowers, they gave better yields

Question 3

vine hybridisation between different species is called

Answer 3

hybridisation

Question 4

Crosses of one vinifera varietal with another is called

Answer 4

Intraspecific vinifera crosses

Question 5

What varietal is cross between Aramon with varietal teinturier

Answer 5

Alicante Bouschet

Question 6

What varietal is cross between Riesling and Madeleine Royale

Answer 6

Muller-Thurgau

Question 7

What is name for pieces of parent plant (stems, roots, leaves) that develop into a new plant when placed in right conditions

Answer 7

Cuttings

Question 8

What part of vine is used for cuttings

Answer 8

hardwood winter cuttings from canes, 30-45 cm in length, stored about 5 C, heat treated (30 min at 50 C) to get rid of pests

Question 9

Bench grafting

Answer 9

indoors

Question 10

what is top grafting

Answer 10

to change cultivars in established vineyard, most common methods are chip-budding and t-budding bud of new varietal inserted on trunk of old one.

Question 11

This vine species has strongly flavored, dark berries, foxy aroma. Not often used for rootstocks

Answer 11

Vitis labrusca

Question 12

This species are principaly used as rootstock (low vigour, surface rooting, early ripening), good resistance to phylloxera

Answer 12

Vitis riparia

Question 13

This species are used for rootstock (vigorous, deep rooting system), good resistance to phylloxera

Answer 13

Vitis rupestris

Question 14

This species are used to control vigour on high fertile soil (as rootstock)

Answer 14

Vitis riparia

Question 15

This species are good for poor soils with limited water (as rootstock)

Answer 15

Vitis rupestris

Question 16

This species are vigorous, deep rooting, high resistance to chlorosis, hybridised to produce lime resistant root stocks

Answer 16

Vitis berlandieri

Question 17

Major drawback of V. berlandieri to be used as rootstock

Answer 17

its cuttings have a poor ability to root so rarely used as pure species.

Question 18

How is called reproductive structure on vine

Answer 18

grape berry, contains seeds which can germinate into young vines.

Question 19

What is epidermis

Answer 19

berry skin, single layer of cells that produce a thin layer called cuticle which provide a waterproof coating and some protection against disease

Question 20

What is pulp made of

Answer 20

pulp is made up of large cells with very thin cell walls which have large spaces (vacuoles) inside them containing juice

Question 21

What is peripheral pulp

Answer 21

located immediately beneath epidermis, contains high proportion of colored pigments, tannins, flavor constituents

Question 22

This part of berry consist of embryo and albumen

Answer 22

seeds

Question 23

What are the main constituents of juice are

Answer 23

water (80%), sugars and other carbohydrates (20%), acids (1%), phenolic compounds (0.1%)

Question 24

What minerals salts are found in grape berry juice

Answer 24

Small amouns of mainly potassium, with some calcium salts. These can buffer (mask) the effects of the acids present.

Question 25

What are sugars

Answer 25

simple carbohydrates. Glucose and fuctose

Question 26

What are pectins

Answer 26

complex carbohydrates, aromatic varieties (gewurzd, viognier) are particularly high. High concentration make difficult to extract, clarify grape juice so they can be breakdown by pectolytic enzymes.

Question 27

How you can break down pectins

Answer 27

by pectolytic enzymes

Question 28

What are main acids found in grape berry

Answer 28

Tartaric and malic acids, found in pulp, organic acids (carbon atoms). Responsible for fresh crisp taste and prevent microbial spoilage.

Question 29

What are secondary acids found in grape berry

Answer 29

citric, ascorbic and acetic acids

Question 30

What are phenolic compounds

Answer 30

group of chemical compounds that affect a wines color, texture, astringency and bitterness. They are synthetised from sugar in the berry.

Question 31

What are catechins and epicatechins

Answer 31

smaller phenolic molecules, they can taste bitter or waxy, or develop bitter taste on oxidation.

Question 32

This phenolic compounds are responsible for color in red wines

Answer 32

Anthocyanins

Question 33

Where anthocyanins are found in grape berry

Answer 33

they are found in pulp cells directly underneath the skins.

Question 34

What is the name of large phenolic compounds that determine body and astringency of wine

Answer 34

Tannins. Important antioxidants and preservatives. They are precursors to aromatic compounds when wines are aged.

Question 35

Chemical composition of grapes is affected by

Answer 35

grape variety terroir viticultural management seasonal variation (vintage)

Question 36

This stage of ripening process extends from formation of bery until veraison.

Answer 36

Hebaceous phase or vegetative period

Question 37

This stage of berry ripening last just few days, marks begining of berry ripening

Answer 37

Veraison

Question 38

This stage of berry ripening lasts 40-60 days. Grapes swell, sugar increase, acidity decrease, berry loses herbaceous flavor, and gains fruity flavors

Answer 38

Maturation or accumulation phase

Question 39

This stage of berry ripening is charecterised by softening of berry which gain large amount of water and increase in weight and volume

Answer 39

Maturation or accumulation phase

Question 40

In this stage of ripening process berry itself stops photosynthesizing, all sugars that accumulate in grape after this stage are photosynthesized in leaves

Answer 40

Veraison

Question 41

In this stage of ripening process berries are small, hard and green, photosynthesise actively and they taste acidic

Answer 41

Hebaceous phase or vegetative period

Question 42

This stage of berry ripening is characterised by rapid increase in glucose and fructose, increasing in phenolic levels

Answer 42

Maturation or accumulation phase

Question 43

This stage of berry ripening is characterised by decrease in acidity, some malic acid is broken down by respiration but concentration is mostly reduced by dillution. Tartaric acid concentraion does not vary greatly

Answer 43

Maturation or accumulation phase

Question 44

This stage of berry ripening is important for production of sweet wines. Fruit becomes shrivelled, lose water, juice becomes more concentrated

Answer 44

Sur-maturation (over-ripe)

Question 45

When grapes reached maximum sugar content and size and the vascular bundles that link them to the rest of the plant cease functioning is called

Answer 45

The physiological maturity of grapes.