Science of Tasting Flashcards
Five different anthocyanins in vinifera
Cyanidin
Petunidin
Delphinidin
Peonidin
Malvidin
Pinot Noir lacks the ability to form this kind of anthocyanin
Acylated anthocyanin
(hence the light color)
These two compounds are responsible for cork taint
TCA: 2, 4, 6 trichloroanisole
TBA: 2,4, 6 Tribromoanisole
Both haloanisoles
Where is Brettanomyces native?
Senne Valley of Belgium
Three spoilage compounds associated with Brett
4-EP (band aid)
4-EG (clove and medicinal)
4-EC (sweaty, horsy)
These two species are responsible for production of acetic acid during and after fermentation
Cluconobacter oxydans
Acetobacter aceti
Max acetic acid level for red wine in the US
1.40 g/l
1.7 if brix at harvest is 28 or higher
What is ethyl acetate?
Esther of acetic acid and ethanol
What is “low redox potential”
Wine favors reduction over oxidation, and volatile sulfur compounds like thiols and thioethers are more likely to appear
What is cysteine
A sulfur containing amino acid that generates Hydrogen sulfide
What causes rotten cabbage, burnt match smell
Methyl mercaptan
What causes onion and rubber odors
Ethyl mercaptan
Most common thioether (cabbage, rubber)
Dimethyl sulfide
Examples of Thiols
4MMP (CS and SB grapes)
3MHA and 3MH (SB Marlborough)
2FM (Furfural, from oak and barrel aging, but also in Champagne)
This aromatic compound gives roses its scent
Beta-damascenone
These men challenged the importance of Beta damascenone as an impact compound in red wine in 2007
Benedicte Pineau, Denis Dobourdieu
Beta Ionone and Alpha-ionone have aromas of this
Floral, like violets and raspberries
Vitispirane is this
A norisoprenoid that smells like crysanthemums, eucalyptus and camphor. Accumulates during bottle aging. Signature of Tawny Port
These things impact TDN in riesling grapes
Water stress
nitrogen deficiency
selection of yeast strain
clone
Isoamyl Acetate
Yeasts produce during fermentation
Banana pear drop, bubblegum
Beaujolais
Lactones
Usually product of winemaking processes like fermentation or oak
Sotolon: maple syrup, fenugreek (vin jaune, madeira, sherry)
Whisky Lactone: cis-3-methyl-4-octanolide (3S, 4S) wines aged in new oak. Cocomut
Dimethyl Sulfide
thioesters: Cabbage and shrimp
lower concentration: corn, black olive, truffle. older Champagne and Chardonnay
Riesling can smell like this:
Red cherry, black currant
Two principal oak lactones
Cis Lactones (american oak, whisky lactones)
Trans Lactones
What is quercotriterpenoside?
released from wood into wine during new oak aging, sweet impression
What is a Maillard reaction
reaction between sugars and amino acids that present toasty aromas
these two acids comprise 90% or more of a wine’s total acidity
Tartaric and Malic
What is a stronger acid: Tartaric or Malic
Tartaric
Typical white wine pH range
Typical red wine pH range
2.9-3.5 (white)
3.3-3.8 (red)
this enzyme breaks down sucrose into glucose and fructose
Invertase
What is gluconeogenisis
conversion of excess malic acid to glucose
Grape tannins (phenols) are detected here
Front of the mouth
These are key non flavonoids in white wines
hydroxybenzoic and hydroxycinnamic acids
This yeast generated phenol can play a role in bitterness in white wine
tyrosol
These white grapes all show intense bitterness compounded by higher alcohol levels
Marsanne
Viognier
Gewurztraminer
High levels of alcohol in wines enhance and supress these characteristics
Enhance: Sweetness and bitterness
Supress: acid and astringency
What is the scientific name for sugar alcohol, or glycerol
polyol
Gruner shows distinct bitterness: t/f
TRUE
