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added some phenol info
==Phenol Production==
Phenols such as 4-vinylphenol (4VP, barnyard, medicinal) and 4-vinylguaiacol (4-VG, clove) can be produced in beer by the decarboxylation of hydoxycinnamic acids, which are found in malt. While both ''Saccharomyces'' and ''Brettanomyces'' strains are capable of converting hydroxycinnamic acids to their vinyl derivatives, ''Brettanomyces'' is also able to reduce these vinyl derivatives to ethyl derivatives. These vinyl derivatives have similar tastes to the ethyl derivatives but have lower flavor thresholds.
{| class="wikitable sortable"
|-
! Phenol !! Phenol Type !! Precursors !!
|-
| 4-vinylphenol (Barnyard, medicinal, band-aid) || Vinyl phenol || P-Courmaric Acid
|-
| 4-vinylguiacol (Clove) || Vinyl phenol || Ferulic Acid
|-
| Vinyl calechol || Vinyl phenol || Caffeic Acid
|-
| 4-ethylphenol (Barnyard) || Ethyl phenol || 4-vinylphenol
|-
| 4-ethylguiacol (Smokey) || Ethyl phenol || 4-vinylguiacol
|-
| Ethyl calechol || Ethyl phenol || Vinyl calechol
|-
|} <ref>[http://www.ahaconference.org/wp-content/uploads/presentations/2008/GregDoss_BrettBrewing.pdf Doss, Greg. Brettanomyces:
Flavors and performance of single and multiple strain
fermentations with respect to time. Presentation at 2008 NHC.]</ref>
==Acid Production==