Introduction To Winemaking

Front 1

What are the major strains of yeast used in Winemaking?

Back 1

Saccharomyces cerevisae
Saccharomyces bayanus
and Wild yeast: many types

Front 2

How do winemakers choose yeast strains?

Back 2

you want a strain that is most resilient.
and think about the type of wine you want to make.

Front 3

How do we control wild yeasts?

Back 3

1) quick inoculation S.cerevisae will dominate
2)Use of SO2, both at the crusher and while wine is ageing.
3)Prevent O2 exposer

Front 4

What happens during alcoholic fermentation?

Back 4

95% of sugar is converted into ethanol and carbon dioxide.
1% Cell Biomass
4% other products
27grams of sugar=3.6 degrees F

Front 5

What does the growth phase of yeast look like?

Back 5

it starts slowly then increases rapidly and as alcohol increases the yeast begin to die.

Front 6

what is the temperature range for healthy fermentation?

Back 6

50F---90F
50F yield fresher fruitier wine

Front 7

How Do we monitor our fermentations?

Back 7

Brix and Temp and days.
on a graph

Front 8

What Nutrients do Yeast Need?

Back 8

Sugars and nitrogenous compounds are the most important yeast nutrients

Front 9

What does YAN stand for?

Back 9

Yeast Assimilable Nitrogen.
it is the amount of nitrogen Yeast can utilize.

Front 10

What two things do we measure when monitoring alcoholic Fermentation?

Back 10

Brix and Temp

Front 11

What is the dominant yeast found on grape skins?

Back 11

Hanseniaspora Uvarum: wild yeast that is bad. can live in 150mg/L SO2

Front 12

When purchasing a yeast for a low alcohol wine with 3% residual sugar, what features might a winemaker select for?

Back 12

Ethanol tolerance
Osmotic tolerance
Varietal
Red or white
acid tolerance
Temperature
MLF
Volatile ester production
Hydrogen Sulfide production

Front 13

What Nutrients do Yeast need?

Back 13

YAN

Front 14

Where do nutrients come from?

Back 14

Amino Acids and Ammonia (which is nitrogen)

Front 15

how much YAN is Needed?

Back 15

need appx 140-160mg/L of Yan to complete a fermentation.
Ideal amount is around 320mg/L of YAN.

Front 16

1g/L Dap=

Back 16

220mg/L of Yan

Front 17

When do you stop adding yeast

Back 17

8-10 brix

Front 18

How Much yeast is needed to complete a fermentation?

Back 18

140-160mg/l of YAN to complete
320 mg/L ideal to complete

Front 19

Why Do we add SO2?

Back 19

1)To manage Polyphenol Oxidase
2)To inhibit unwanted flora(wild yeast)
3)To select wanted flora(Yeast)
4)To enhance settling (due to lower microbiological growth)

Front 20

Rate of SO2 addition depends on:

Back 20

0-50ppm for excellent fruit
50-75mg/L average/slightly damaged
100ppm for severe damage

Front 21

Pectolytic Enzymes

Back 21

Break down pectin

Front 22

Bentonite

Back 22

aids in compaction of soids drops the lees to the bottom

Front 23

Oxidative

Back 23

allows oxygen to contact with the fruit during processing.
turns brown due to Polyphenol Oxidase

Front 24

Reductive

Back 24

reduces oxygen contact
maintains higher esters and fruity components.

Front 25

Basic Measurements

Back 25

Brix
pH: effectivenes of acid
TA: Titratable Acidity
Free and Total SO2

Front 26

Settling

Back 26

enzymes are added
to drop solids out of the wine
Bentonite, SO2 (stops microbes)
juice is then racked.

Front 27

what is it called when you age on the yeast?

Back 27

Sur Lie ageing
it adds a doughy toasty flavor

Front 28

most planted grape on earth

Back 28

Arien

Front 29

what do you test for at harvest:

Back 29

Brix
pH
TA

Front 30

what enzymes break down the skin for better extraction

Back 30

Glycolytic Enzyme