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1. 1 Common Wine Defects
2. 2 Common Wine Defects
3. 3 Glass # 1: 12% Ethanol
4. 4 Glass # 1: 12% Ethanol Warm, sweet
Critical ingredient of the wine’s matrix
Next glasses = pure compounds spiked in 12% ethanol
5. 5 Glass # 2: Acetaldehyde
6. 6 Glass # 2: Acetaldehyde Pungent, fruity, overripe apple…
Oxidation of ethanol
Threshold ~ 100 mg/L (~ 100 ppm)
7. 7 Glass # 3: Acetic Acid
8. 8 Glass # 3: Acetic Acid Vinegar, pungent…
Microbial oxidation of ethanol or conversion from sugars
Threshold ~ 0.70 g/L (~ 700 ppm; ~ 0.070%)
9. 9 Glass # 4: Ethyl acetate
10. 10 Glass # 4: Ethyl acetate Solvent, nail polish…
Some “wild” yeasts and acetic bacteria
Threshold ~ 150 mg/L (~150 ppm)
11. 11 Glass # 5: 4EP / 4EG(4-Ethylphenol / 4-Ethylguaiacol)
12. 12 Glass # 5: 4EP / 4EG(4-Ethylphenol / 4-Ethylguaiacol) Phenol, Band Aid®, leather, clove...
Brettanomyces byproducts
Thresholds
4EP ~ 400 ug/L
(~ 400 ppb)
4EG ~ 50 ug/L
(~ 50 ppb)
13. 13 Glass # 6:Methylmercaptan / Dimethyldisulfide
14. 14 Glass # 6:Methylmercaptan / Dimethyldisulfide Natural gas, rotten cabbage / cooked vegetable…
Yeast byproducts
Thresholds
MeSH ~ 1.5 ug/L
(~ 1.5 ppb)
DMDS ~10 ug/L
(~10 ppb)
15. 15 Glass # 7: Dimethylsulfide (DMS)
16. 16 Glass # 7: Dimethylsulfide (DMS) Canned corn, asparagus, olive, truffle… fruit enhancer
Degradation of S-methylmethionine or reduction of DMSO
Threshold ~ 20 ug/L
( ~ 20 ppb)
17. 17 Glass # 8: TCA (2,4,6-Trichloroanisole)
18. 18 Glass # 8: TCA (2,4,6-Trichloroanisole) Moldy, cork taint
Mold byproduct
Threshold ~ 2-6 ng/L
( ~ 2-6 ppt)
19. 19
20. 20 Common Wine Defects
21. 21