Prac Book

Question 1

what do you measure to ascertain grape maturity?

Answer 1

• the concentration of TSS - total soluble sugars
• the concentration of T.A - total titratable acids
• ph

Question 2

what is saccharomyces?

Answer 2

wine yeasts… a genus of fungi

Question 3

what are the primary sugars that create the “food” for the yeasts to feed on?

Answer 3

fructose and glucose

Question 4

what are the two main acids in grapes?

Answer 4

malic and tartaric

Question 5

what two methods/apparatus are used to determine the concentration of total soluble sugars?

Answer 5

hydrometer and refractometer

Question 6

what does it mean if the wine is fermented dry?

Answer 6

fermented to the point where no more sugars are available

Question 7

why is baume useful?

Answer 7

it is a good guide to the alcohol (ethanol)% that will be in the finished wine if wine is fermented dry

Question 8

the relationship of baume to ethanol is what?

Answer 8

1 - 1.1… eg, roughly the same with 10% variance

Question 9

what is the symbol/sign for baume?

Answer 9

Be

Question 10

High pH = ?

Answer 10

low acid

Question 11

list the baume degrees (Tss - sugar readings) range for the below wines: 
White table 
red table
sweet table 
dessert (botrytis)

Answer 11

W: 12-14
R: 12-14
S: 13-16
D: 17-22

Question 12

list the Total titratable acidity of malic and tartaric acid (T.A. g/L) of the below wines: 
White table 
red table
sweet table 
dessert (botrytis)

Answer 12

W: 6-8
R: 5-9
S: 7-9
D: 6-9

Question 13

list the standard pH of the below wines: 
White table 
red table
sweet table 
dessert (botrytis)

Answer 13

W: <3.3
R: <3.4
S: <3.4
D: <3.6

Question 14

baume is a measure of what?

Answer 14

sugar concentration in grape juice

Question 15

baume is used in which countries to measure sugar concentration in grape juice’?

Answer 15

Aus and France

Question 16

what are some other measures of fermentable sugar concentration in grape juice and which nations use them?

Answer 16

Brix = NZ and America 
Oechsle = Germany and some other parts of Europe.

Question 17

what is the conversion of baume to Brix?

Answer 17

1 baume = 1.8 brix

Question 18

what does ppm stand for?

Answer 18

parts per million

Question 19

what is an “okay” amount of acids in wine? what is a lot?

all per litre

Answer 19

1-2 grams per litre is okay

5-6 grams of acid per litre is a lot

Question 20

what is o Saccharomyces cerevisiae (S)

Answer 20

a species of yeast

Question 21

how much fruit was picked at dookie winery?

Answer 21

819 + 720 = 1539

Question 22

how was the fruit delivered to the winery?

Answer 22

10 kg picking bins

Question 23

was the machine at dookie a de-stemmer/crusher or a crusher/de-stemmer? why?

Answer 23

de-stemmer/crusher

we wanted to reject stalks and stems because crushing stems may result in more bitterness

Question 24

what is the approx recovery rate of juice per tonne from the grapes harvested?

Answer 24

1 tonne = 650 L juice

in some white grape varieties you can get 700 L

Question 25

what is the key difference between early stages of red and white wine production?

Answer 25

Red: skins are kept in must and fermentation happens while in contact with the skins White: skins are removed for the fermentation process

Question 26

what is inoculation?

Answer 26

adding good microorganisms to the wine to ward off against spoilage etc

Question 27

what was the strain of yeast used at dookie?

Answer 27

Vitilevure - Syrah

Question 28

what is a stuck ferment?

Answer 28

when the wild yeast only ferments must down to about 3/4 baume. hard to restart the ferment and the ferment is only 3/4 done

Question 29

what changes take place to the must in a ferment?

Answer 29

``` the temp will rise sugar level (baume) will drop as yeast eat sugars ```

Question 30

how much sulphur dioxide SO2 did we add to our must

Answer 30

30 ppm

Question 31

we added oak chips, what does this do?

Answer 31

they contain tannin so it helps with colour and structure

Question 32

what is the "cap" in the fermenting must?

Answer 32

the solid mass of skins on top

Question 33

how much yeast did we add to the must to start fermentation?

Answer 33

150 g added to 500L

Question 34

why do we plunge and pump-over?

Answer 34

- to oxidise.. - this also keeps the cap wet and extracts flavours and tannins - also airates "must" to give yeast oxygen - releases heat - need to do this otherwise yeasts die

Question 35

what does yeast create during the fermentation process?

Answer 35

- heat - CO2 - alcohol

Question 36

what was the baume on the 25/2?

Answer 36

11.8

Question 37

what is the optimal temp for malolactic fermentation?

Answer 37

20 degrees

Question 38

how many times a day did we plunge our must?

Answer 38

2

Question 39

what is hectolitre?

Answer 39

100 litres

Question 40

what does malolactic fermentation do?

Answer 40

converts malic acid into lactic acid

Question 41

what were the two types of "press" at dookie?

Answer 41

basket press | Airbag press - compress air (pneumatic)

Question 42

what is the difference in processes when pressing reds and whites?

Answer 42

reds: you press the fermented must after alcoholic fermentation has occurred whites: you press the bunches/grapes before fermentation

Question 43

if you were pressing riesling grapes instead of Shiraz grapes, what sort of press might you use and why?

Answer 43

airbag press | because it allows us to strain/drain juice away from skins

Question 44

what is the optimal fermenting temp?

Answer 44

28 degrees

Question 45

why is refrigeration and temp control vital in winemaking?

Answer 45

because it is imperative to controlling fermentation... if ferment is too hot/cold, yeast start to die

Question 46

what does dookie use to inoculate MLF

Answer 46

direct addition of lactic acid bacteria

Question 47

what is the required environment before MLF is conducted?

Answer 47

- temp has to be right | - primary fermentation has to be going first

Question 48

what are the benefits of stainless steel barrels?

Answer 48

- is an inert vessel and can be a closed system with no oxygen - easy to clean - good for temp control?

Question 49

what are the downsides of stainless steel barrels?

Answer 49

- it has to be completely full for it to act as a closed vessel with no oxygen coming in - while there are variable capacity stainless steel barrels, this can result in them not being the greatest seal long term

Question 50

in a year, how much wine is lost due to evaporation over long term storage?

Answer 50

5%

Question 51

what methods are undertaken to maintain the integrity of wine over long term storage

Answer 51

- keep cool - properly sealing of storage vessel - topping up

Question 52

what is classified as long term storage of wine

Answer 52

several months

Question 53

why does wine need to be kept cool during storage, what is the ideal temp?

Answer 53

ideal temp is 20 degrees | - because heat is the enemy due to oxidization as heat excites oxygen molecules

Question 54

why are oak barrels used for maturation... what is this referred as?

Answer 54

to get oak characters into the wine | toasting

Question 55

what are the characters of: light medium heavy toasting?

Answer 55

medium: caramel, vanilla heavy: chocolate, coffee, smokey, char-rey

Question 56

what is AO?

Answer 56

American oak

Question 57

what kinds of oaks are used and what characteristic comes from the respective oak?

Answer 57

French: soft, spicy vanilla American: coconut Fine-grain: slow microoxygenation

Question 58

what else can winemakers do to achieve oak characteristics without storage in oak barrels

Answer 58

add: | - oak chips, planks, cubes, squares, shavings, powder, staves

Question 59

what is the finest form of filtration? why is it the finest?

Answer 59

sterile filtration... | no microorganisms that will cause spoilage can get through

Question 60

what is filtration? why do we do it?

Answer 60

passing the wine through various sized filters | - to improve appearance

Question 61

what is clarification used for? how is it done?

Answer 61

appearance... eg to get rid of cloudy appearance | adding of an agent that will assist with getting rid of the sediment

Question 62

what is fining?

Answer 62

adding agents such as egg whites that will settle to the bottom of the vessel and take harsh tannins and acids to the bottom to fine the wine

Question 63

what are the negatives of filtration?

Answer 63

could strip flavour and some thing is unnatural

Question 64

what is racking?

Answer 64

separating the wine juice from the sediment (skins, lees) | racking off clear juice from sediment

Question 65

what can harm the quality of the wine prior to and during bottling?

Answer 65

- oxidisation - excessive heat - contamination

Question 66

what are the standard sizes of oak barrels and what are they called?

Answer 66

Barrique - 225 L Hogs Head - 300 L Puncheon - 500 L

Question 67

what are the major pathogens of the grapevine? | what are the major groups of pathogens?

Answer 67

- fungal disease - powdery mildew, downy mildew and botrytis - Bacteria such as phylloxera - Viral disease: Eytupa dieback - nematodes in soil viruses, fungi, bacteria, protozoa, worms