slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Lecture 17: Aging PowerPoint Presentation
Download Presentation
Lecture 17: Aging

Loading in 2 Seconds...

play fullscreen
1 / 33

Lecture 17: Aging - PowerPoint PPT Presentation


  • 118 Views
  • Uploaded on

Lecture 17: Aging. Reading Assignment: Text, Chapter 10, pages 382-415. AGING: As a means of achieving stability. Aging: To Achieve Stability. To allow reactions that are going to happen to occur before bottling Polymerization of tannin Polymerization of pigment

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Lecture 17: Aging' - wilda


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide2

Reading Assignment:

Text, Chapter 10, pages 382-415

slide3

AGING:

As a means of achieving stability

aging to achieve stability
Aging: To Achieve Stability
  • To allow reactions that are going to happen to occur before bottling
    • Polymerization of tannin
    • Polymerization of pigment
    • Stabilization of color
    • Loss of volatile esters
slide6

AGING:

To correct a problem

aging to correct a problem
Aging: To Correct a Problem
  • Allow “negatives” to disappear
    • Volatilization
    • Hydrolysis
    • Oxidation
    • Precipitation
    • Other Chemical reactions
slide8

AGING:

As stylistic

aging as stylistic
Aging: As Stylistic
  • “Oxidative” versus “reductive” aging
  • Allow formation of new characters
  • Addition of new characters from cooperage
  • Addition of new characters from yeast lees/autolysis
  • Increase/Decrease complexity depends upon varietal/composition
slide11
Time

Different reactions will occur at different rates.

A steady state value may or may not be reached.

[Compound]

Time

aging variables1
Aging Variables
  • Time
  • Temperature
temperature
Temperature

Faster at Higher Temperature

Slower at Higher Temperature

Temperature Independent

aging variables2
Aging Variables
  • Time
  • Temperature
  • Oxygen
oxygen exposure leads to
Oxygen Exposure Leads To:
  • Polymerization of phenolics
    • Good: softens astringency
    • Bad: too much loss of color
  • Browning/Pinking
    • May be desirable or neutral (reds)
    • May be undesirable (whites)
  • Acetaldehyde
  • Stabilized color
  • Oxidized flavors
acetaldehyde formation
Acetaldehyde Formation

OH

O

+ 02

+ H2O2

R

OH

O

R

OH

O

H2O2 + H3C-CH2

H3C-CH + 2H2O

stabilization of color
Stabilization of Color

Reaction of oxygen with anthocyanins leads to polymerization and stabilization of red color.

control of oxygen exposure
Control of Oxygen Exposure
  • Use inert gas flush (N2, CO2)
  • Limit headspace
    • Top-off barrels
  • Monitor saturations
air saturations
Air Saturations
  • One “saturation” = 6 mL O2/L
  • Capacity for O2 is dependent upon the phenolic composition
  • A single saturation occurs with each air exposure
    • Racking
    • Fining
    • Filtration
    • Centrifugation
    • Movement to tank/barrel
aging variables3
Aging Variables
  • Time
  • Temperature
  • Oxygen
  • Cooperage
cooperage
Cooperage
  • Glass
  • Stainless steel
  • Wood
wood variables
Wood Variables
  • Source of wood
    • French
    • American
    • Other
  • Aging of wood
  • Toasting level
  • Number of times it has been used
  • Barrel, Staves, Chips
slide23
Wood
  • Allows limited oxygen exposure
  • Allows some evaporative loss
  • Adds nuances
  • Surface area versus volume of wine important
aging variables4
Aging Variables
  • Time
  • Temperature
  • Oxygen
  • Cooperage
  • Yeast lees
yeast lees
Yeast Lees
  • Yeast autolysis adds flavors
    • Long chain esters
    • Stimulates Malolactic Fermentation
  • Activity of yeast enzymes continues post-lysis
  • Impacts mouth feel
aging variables5
Aging Variables
  • Time
  • Temperature
  • Oxygen
  • Cooperage
  • Yeast lees
  • pH
slide27
pH
  • Affects rates of some reactions
  • Phenolic oxidations 9 times faster at pH 4.0 versus pH 3.0
  • Affects microbial persistence and activity
aging variables6
Aging Variables
  • Time
  • Temperature
  • Oxygen
  • Cooperage
  • Yeast lees
  • pH
  • Catalysts
catalysts
Catalysts
  • Metal ions can increase rates of some chemical reactions
aging variables7
Aging Variables
  • Time
  • Temperature
  • Oxygen
  • Cooperage
  • Yeast lees
  • pH
  • Catalysts
  • Chemical composition of wine
chemical composition of wine
Chemical Composition of Wine

It’s what in there that counts!

packaging
Packaging
  • Bottling
    • Sterile
    • Non-sterile
  • Closure
    • Cork
    • Synthetic cork
    • Screw cap
    • “Bag-in-box”