Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C....
-
Upload
bartholomew-hubbard -
Category
Documents
-
view
213 -
download
0
Transcript of Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C....
![Page 1: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/1.jpg)
Impact of Brettanomyces on Wine Quality
Lucy JosephDepartment of Viticulture and Enology
U.C. Davis
![Page 2: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/2.jpg)
Introduction• Brettanomyces is considered to be the
primary spoilage yeast in finished wine
• However, many consumers and critics like the complexity that is derived from Brett growth in wine
![Page 3: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/3.jpg)
Compounds Produced by Brett in Wine
• Signature spoilage compounds - ethyl phenols, vinyl phenols
• Other spoilage compounds – acetic acid, ethyl acetate, fatty acid, carboxylic acid
• Compounds that are positive – Esters, higher alcohols, terpenes
![Page 4: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/4.jpg)
Strain Collection
![Page 5: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/5.jpg)
Alcohol Aldehyde Ester Ethyl Phenol Fatty Acid Terpene Vinyl Phenol
Isoamyl Nonanal Ethyl butanoate
4-ethylphenol Butanoic Ocimene 4-vinylphenol
Amyl (active)
Pentyl formate
4-ethylguaiacol Heptanoic Bisabolene 4-vinylguaiacol
2-ethylhexanol
Ethyl isovalerate
Undecanoic
Phenethyl Ethyl valerate
2-methoxyphenyl
Ethyl 2-methylbutyrate
Octyl-butyrate
Amyl-octanoate
Phenethyl formate
Fruit/floral chemical
Artificial fruit/floral
Artificial fruit/floral
Chemical, smoke/spice
Sweaty/rotten cheese
Floral resin spice
Spicy wood smoke medicinal
![Page 6: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/6.jpg)
Initial Screen• Defined medium was used• Supplemented with amino acids• All strains will make 4EP and 4EG
with coumaric and ferulic acids
![Page 7: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/7.jpg)
Positive and Negative Perception
![Page 8: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/8.jpg)
Selection for Test in Wine
• Descriptors, intensity, and likability used to score strains
• Out of the initial 83 that were successfully screened in the initial screen, 17 were chosen as “positive” and 5 as “negative”
![Page 9: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/9.jpg)
Summary of Aroma for Strains Tested in Wine
![Page 10: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/10.jpg)
SPME-GCMS• These strains were also screened chemically• Used defined medium supplemented with – Aromatic amino acids– Cinnamic acids and aromatic amino acids
• Goal was to identify strains that produced low negative characters
![Page 11: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/11.jpg)
Cluster Analysis of Strains
![Page 12: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/12.jpg)
Important Compounds
That Determine DifferencesWith Amino
Acids
![Page 13: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/13.jpg)
Relative Concentration of Compounds in “Most Liked” Strains – Amino Acid
Supplemented• Phenethyl acetate – Sweet, honey, floral rosy• Ethyl decanoate – sweet, waxy, fruity, apple• Ethyl hexanoate – sweet, fruity, pineapple, waxy
green banana• Ethyl octanoate – fruity, wine, waxy, sweet• 2-phenylethanol – floral, rose, rose water• Octanoic acid – fatty, rancid oil, cheesy• Ethyl acetate – nail polish remover, solvent• 3-methylbutanoic acid – sour, stinky feet, sweaty, cheese • Decanoic acid – rancid, sour, fatty, citrus• 2-phenylacetaldehyde – honey, sweet, rose, green, grassy
![Page 14: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/14.jpg)
Important Compounds
That Determine Differences
With Cinnamic
and Amino Acids
![Page 15: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/15.jpg)
Relative Concentration of Compounds in “Most Liked” Strains – Amino Acid and Phenolic
Acid Supplemented
• Ethyl octanoate – fruity, wine, waxy, sweet• 2-phenylethanol – floral, rose, rose water• Ethyl decanoate – sweet, waxy, fruity, apple• 4-ethylphenol – medicinal, Band-Aid, barnyard• 4-ethylguaiacol – spicy, smoky, phenolic, clove• Octanoic acid – fatty, rancid oil, cheesy• Decanoic acid – rancid, sour, fatty, citrus• Phenethyl acetate – Sweet, honey, floral rosy• Ethyl acetate – nail polish remover, solvent• Decanol – waxy, floral, orange, sweet
![Page 16: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/16.jpg)
![Page 17: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/17.jpg)
![Page 18: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/18.jpg)
![Page 19: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/19.jpg)
![Page 20: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/20.jpg)
![Page 21: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/21.jpg)
Wine Descriptions (under $25)• rose petal and earl grey tea, baking spices• pepper, baking spices, flowers• violets and spices• bittersweet iris-like, brioche as well as butter• black licorice and roasted herbs• mocha and anise• spice, licorice and wild bush, mineral • peppery spice, dust • fruit with nutty, savory complexity• popcorn, brioche, grilled nuts• smoke-accented aromas, cola and spices
![Page 22: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/22.jpg)
Wine Descriptions ($25 to $50)• forest floor, black pepper, moss covered tree bark and game • potpourri and orange zest, with a subtle smoky overtone; spicy
floral, loamy earth, cedar and savory herb • Sappy, spice-accented, medicinal cherry note, with clinging
spicecake and cracked pepper• musky aromas, smoked meat, bacon fat and licorice and chocolate
flavors• smoky, savory; smoke and bacon with chocolaty finish; violets and
baking spices• bread crust, coffee and dark chocolate and a touch of spices• crushed rock, camphor, and a hint of pen ink• smoked meat, cracked pepper, tobacco and masses of crushed
stone / mineral• creosote, minerals, and toasty oak• incense and rose oil; sandalwood and tea leaf
![Page 23: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/23.jpg)
Wine Descriptions ($50 to $75)• black truffles, roasted meats, charcuterie,
incense, roasted herbs and licorice; spice-accented aromas and potpourri, hint of spicecake; charcoal notes, long, tarry finish
• graphite, savory herbs, white flowers, orange peel, spices, nutmeg, clove; mineral and cedar; violet, grilled meat and tar, cassis and licorice
• bay leaf, sage, anise, toast and chocolate, mineral and earth; roasted coffee, herb; earthy black currant and fig, and charcoal-infused fruit
• exotic, smoky oak; sage and underbrush, even a touch of gun oil
![Page 24: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/24.jpg)
Using Descriptors
• Wines were purchased from an online site by searching using descriptors from the aroma wheel
• These wines were tested for the presences of microbes by plating, microscopy, and qPCR
• Wines were also analyzed for 4EP and 4EG
![Page 25: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/25.jpg)
What We Found• 35 wines were selected• 17 had viable lactic acid bacteria by plating
(49%)• 9 had viable Brett by plating • An additional 5 had Brett by qPCR• Another 4 had Brett by 4EP and 4EG levels• A total of 18 showed evidence of Brett (51%)• All of the wines were positive for microbial
contamination
![Page 26: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/26.jpg)
![Page 27: Impact of Brettanomyces on Wine Quality Lucy Joseph Department of Viticulture and Enology U.C. Davis.](https://reader038.fdocuments.us/reader038/viewer/2022110321/56649cec5503460f949b83b1/html5/thumbnails/27.jpg)