|
Stuck
Fermentation
|
The
yeast died before fermentation completed
|
Keep
fermentation temp. below 90 degrees; dilute overripe fruit with water to 25
Brix; add nitrogen (DAP) and SuperFood;
use vigorous yeast like Prise de Mousse
|
|
Cooked
Flavors
|
Fermentation
temperatures too high; overripe grapes; too many raisins
|
Ferment
whites at 60 deg. Or less; ferment reds at 85 degrees or less; avoid
overripe fruit
|
|
Burnt
match odor
|
Sulfur
dioxide gas
|
Keep
free SO2 to less than 40ppm; use less SO2 in wines with low pH values
|
|
Sherry
or Madeira odors
|
Oxidized
wine
|
Keep
all wine storage containers full and tightly sealed; use moderate amt. Of
sulfur dioxide; avoid pumps with leaky shaft seals and avoid air leaks in
pump suction lines
|
|
Swampy
odors
|
Bad
corks
|
Try
changing cork suppliers
|
|
Rotten
egg odors
|
Hydrogen
sulfide gas
|
Avoid
grapes with excessive sulfur residues; avoid Montrachet
yeast; add nitrogen and nutrients early; avoid hot fermentation
|
|
Vinegar
and fingernail polish odors
|
Acetic
acid and ethyl acetate produced by Acetobacter
bacterium
|
Keep
containers full; use moderate amt. Of sulfur dioxide but Acetobacter tolerates SO2; remove pomace
promptly; keep winery clean
|
|
Rancid
butter odor
|
Excessive
amount of diacetyl
|
Inoculate
with ML bacteria early; control ML fermentation w/ SO2
|
|
Moldy
or mildew odor
|
Moldy
barrels; rotten fruit; mold in hoses & equipment
|
Avoid
empty barrels/maintain them properly; avoid rotten, moldy grapes; hang
hoses to dry completely; keep winery clean
|
|
Barnyard,
horsy, mousy or wet-dog odors
|
Fermentation
products produced by Brettanomyces film yeast
|
Keep
containers full; maintain 30 ppm SO2; avoid
unknown/used barrels; get rid of dirty smelling barrels; keep winery clean
|