Difference between revisions of "Beer Sensory"

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[[Media:SCP BeerScoreSheet.pdf|BJCP Score Sheet (2017)]]
 
[[Media:SCP BeerScoreSheet.pdf|BJCP Score Sheet (2017)]]
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==Descriptor Definitions==
 +
When the following items are noticed in a beer, it is generally a sign of some error in the brewing process, but this is not always the case.
  
 
===Acetaldehyde===
 
===Acetaldehyde===
:– Green apple-like aroma and flavor.
+
:''– Green apple-like aroma and flavor.''
 +
This flavor and aroma is intentionally present in Budweiser at a very low level.
 
===Alcoholic===
 
===Alcoholic===
:– The aroma, flavor, and warming effect of ethanol and higher alcohols. Sometimes described as hot.
+
:''– The aroma, flavor, and warming effect of ethanol and higher alcohols. Sometimes described as hot.''
 
===Astringent===
 
===Astringent===
:– Puckering, lingering harshness and/or dryness in the finish/aftertaste; harsh graininess; huskiness.
+
:''– Puckering, lingering harshness and/or dryness in the finish/aftertaste; harsh graininess; huskiness.''
 
===Diacetyl===
 
===Diacetyl===
:– Artificial butter, butterscotch, or toffee aroma and flavor. Sometimes perceived as a slickness on the tongue.
+
:''– Artificial butter, butterscotch, or toffee aroma and flavor. Sometimes perceived as a slickness on the tongue.''
 
===DMS (dimethyl sulfide)===
 
===DMS (dimethyl sulfide)===
:– At low levels a sweet, cooked or canned corn-like aroma and flavor.
+
:''– At low levels a sweet, cooked or canned corn-like aroma and flavor.''
 +
:'''Chemical: dimethyl sulfide'''
 +
 
 
===Estery===
 
===Estery===
:– Aroma and/or flavor of any ester (fruits, fruit flavorings, or roses).
+
:''– Aroma and/or flavor of any ester (fruits, fruit flavorings, or roses).''
 
===Grassy===
 
===Grassy===
:– Aroma/flavor of fresh-cut grass or green leaves.
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:''– Aroma/flavor of fresh-cut grass or green leaves.''
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===Light-Struck===
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:''– Similar to the aroma of a skunk.''
  
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Lightstruck, or "skunked" or "skunky", beer
  
===Light-Struck===
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Leave a clear bottle of beer (Rolling Rock) in the sunlight for 30 mins or expose to UV light source. Some beers use chemically modified hop extracts to prevent the formation of this off-aroma.
:– Similar to the aroma of a skunk.
+
 
 +
Any beer with hops can produce a skunky aroma (mercaptan) "3-methylbut-2-ene-1-thiol" (MBT)
 +
 
 +
References
 +
:Burns, C. S., Heyerick, A., De Keukeleire, D., and Forbes, M. D. E. Mechanism for formation of the lightstruck flavor in beer revealed by time-resolved electron paramagnetic resonance. Chem. Eur. J. 21:4554-4561, 2007.
 +
 
 +
:Huvaere, K., Andersen, M. L., Skibsted, L. H., Heyerick, A., and De Keukeleire, D. Photooxidation degradation of beer bittering principles: A key step on the route to lightstruck flavor formation in beer. J. Agric. Food Chem. 53:1489-1494, 2005.
 +
 
 +
:Huvaere, K., Andersen, M. L., Storme, M., Bocxlaer, J. V., Skibsted, L. H., and De Keukeleire, D. Flavin-induced photodecomposition of sulfur-containing amino acids decisive in the formation of beer lightstruck flavor. Photochem. Photobiol. Sci. 5:961-969, 2006.
  
 
===Metallic===
 
===Metallic===
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===Oxidized===
 
===Oxidized===
 
:– Any one or combination of stale, winy/vinous, cardboard, papery, or sherry-like aromas and flavors.
 
:– Any one or combination of stale, winy/vinous, cardboard, papery, or sherry-like aromas and flavors.
 +
 +
Open a very cold beer and pour out ~ 20 mL (~ the neck of a std bottle)
 +
 +
Darker beers display a "cardboard" oxidation aroma
 +
 +
Hoppy beers loose the hop aroma
 +
 +
:'''Chemical: trans-2-nonenol'''
  
 
===Phenolic===
 
===Phenolic===
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===Vegetal===
 
===Vegetal===
 
:– Cooked, canned, or rotten vegetable aroma and flavor (cabbage, onion, celery, asparagus, etc.)
 
:– Cooked, canned, or rotten vegetable aroma and flavor (cabbage, onion, celery, asparagus, etc.)
 +
:Also see DMS
  
 
===Yeasty===
 
===Yeasty===
 
:– A bready, sulfury or yeast-like aroma or flavor.
 
:– A bready, sulfury or yeast-like aroma or flavor.
 
===Oxidation===
 
Open a very cold beer and pour out ~ 20 mL (~ the neck of a std bottle)
 
 
Darker beers display a "cardboard" oxidation aroma
 
 
Hoppy beers loose the hop aroma
 
 
===Lightstruck===
 
Lightstruck, or "skunked" or "skunky", beer
 
 
Leave a clear bottle of beer (Rolling Rock) in the sunlight for 30 mins or expose to UV light source. Some beers use chemically modified hop extracts to prevent the formation of this off-aroma.
 
 
Any beer with hops can produce a skunky aroma (mercaptan) "3-methylbut-2-ene-1-thiol" (MBT)
 
 
References
 
:Burns, C. S., Heyerick, A., De Keukeleire, D., and Forbes, M. D. E. Mechanism for formation of the lightstruck flavor in beer revealed by time-resolved electron paramagnetic resonance. Chem. Eur. J. 21:4554-4561, 2007.
 
 
:Huvaere, K., Andersen, M. L., Skibsted, L. H., Heyerick, A., and De Keukeleire, D. Photooxidation degradation of beer bittering principles: A key step on the route to lightstruck flavor formation in beer. J. Agric. Food Chem. 53:1489-1494, 2005.
 
 
:Huvaere, K., Andersen, M. L., Storme, M., Bocxlaer, J. V., Skibsted, L. H., and De Keukeleire, D. Flavin-induced photodecomposition of sulfur-containing amino acids decisive in the formation of beer lightstruck flavor. Photochem. Photobiol. Sci. 5:961-969, 2006.
 
  
 
===Snif recognition===
 
===Snif recognition===

Latest revision as of 13:54, 15 April 2018

This is a page that describes activities related to off-flavor/off-aromas in beer.

BJCP Score Sheet (2017)

Descriptor Definitions

When the following items are noticed in a beer, it is generally a sign of some error in the brewing process, but this is not always the case.

Acetaldehyde

– Green apple-like aroma and flavor.

This flavor and aroma is intentionally present in Budweiser at a very low level.

Alcoholic

– The aroma, flavor, and warming effect of ethanol and higher alcohols. Sometimes described as hot.

Astringent

– Puckering, lingering harshness and/or dryness in the finish/aftertaste; harsh graininess; huskiness.

Diacetyl

– Artificial butter, butterscotch, or toffee aroma and flavor. Sometimes perceived as a slickness on the tongue.

DMS (dimethyl sulfide)

– At low levels a sweet, cooked or canned corn-like aroma and flavor.
Chemical: dimethyl sulfide

Estery

– Aroma and/or flavor of any ester (fruits, fruit flavorings, or roses).

Grassy

– Aroma/flavor of fresh-cut grass or green leaves.

Light-Struck

– Similar to the aroma of a skunk.

Lightstruck, or "skunked" or "skunky", beer

Leave a clear bottle of beer (Rolling Rock) in the sunlight for 30 mins or expose to UV light source. Some beers use chemically modified hop extracts to prevent the formation of this off-aroma.

Any beer with hops can produce a skunky aroma (mercaptan) "3-methylbut-2-ene-1-thiol" (MBT)

References

Burns, C. S., Heyerick, A., De Keukeleire, D., and Forbes, M. D. E. Mechanism for formation of the lightstruck flavor in beer revealed by time-resolved electron paramagnetic resonance. Chem. Eur. J. 21:4554-4561, 2007.
Huvaere, K., Andersen, M. L., Skibsted, L. H., Heyerick, A., and De Keukeleire, D. Photooxidation degradation of beer bittering principles: A key step on the route to lightstruck flavor formation in beer. J. Agric. Food Chem. 53:1489-1494, 2005.
Huvaere, K., Andersen, M. L., Storme, M., Bocxlaer, J. V., Skibsted, L. H., and De Keukeleire, D. Flavin-induced photodecomposition of sulfur-containing amino acids decisive in the formation of beer lightstruck flavor. Photochem. Photobiol. Sci. 5:961-969, 2006.

Metallic

– Tinny, coiny, copper, iron, or blood-like flavor.

Musty

– Stale, musty, or moldy aromas/flavors.

Oxidized

– Any one or combination of stale, winy/vinous, cardboard, papery, or sherry-like aromas and flavors.

Open a very cold beer and pour out ~ 20 mL (~ the neck of a std bottle)

Darker beers display a "cardboard" oxidation aroma

Hoppy beers loose the hop aroma

Chemical: trans-2-nonenol

Phenolic

– Spicy (clove, pepper), smoky, plastic, plastic adhesive strip, and/or medicinal (chlorophenolic).

Solvent

– Aromas and flavors of higher alcohols (fusel alcohols). Similar to acetone or lacquer thinner aromas.

Sour/Acidic

– Tartness in aroma and flavor. Can be sharp and clean (lactic acid), or vinegar-like (acetic acid).

Sulfur

– The aroma of rotten eggs or burning matches.

Vegetal

– Cooked, canned, or rotten vegetable aroma and flavor (cabbage, onion, celery, asparagus, etc.)
Also see DMS

Yeasty

– A bready, sulfury or yeast-like aroma or flavor.

Snif recognition