CH 14 : Maturation Flashcards
Why would a winemaker expose their young red wine to oxygen?
to develop more colour stability and intensity
How does oxygen exposure develop colour stability in the wine?
it causes an oxygen reaction where anthrocyanins and tannins bind to each other, protecting the anthrocyanin from SO2 bleaching or colour leeching associated with lees.
why is red wine generally matured for longer than white wine?
during ageing, especially for vessels that allow oxygen ingress, the tannin in red wine allow it to withstand a higher level of oxygen exposure before the effects are evident relative to white wine
How can oxygen exposure during Maturation negatively affect the wine?
it can allow spoilage bacteria, like brettanomyces and acetic acid, to develop
at what temperatures are white and red wines generally stored?
red 12-16C
white 8-12C
How do humidity levels affect maturation?
low humidity increases the rate of wine loss when wines are aged in permeable vessels. This requires more topping up to avoid ullage, a costly process for both labour and resources.
key difference between French and American oak
- American oak has high levels of lactones and imparts more flavour intensity
- European oak imparts more tannin
- American oak grows more quickly
- American oak is cheaper
- European oak must be split, American can be sawed
How does grain of wood in barrels affect the maturation process?
tightly grained wood emerges from slower growth. used in cooperage, it slows down the extraction of flavour/aroma compounds
How long does wood need to be seasoned for before becoming a barrel?
2-3 years
What is autolysis
the breakdown of dead yeast cells which imparts aromas, body, and texture to the wine
why are wines blended
balance
consistency
style
complexity
minimise faults
volume
price
when is blending done?
before stabilisation
