B-400.25.131 [2020-10] p-Coumaric Acid and Ferulic Acid
Coumaric acid (trans-2-hydroxycinnamic acid) and ferulic acid (3-methoxy-4- hydroxycinnamic acid) belong to a group of substances known as phenolcarboxylic acids and are derived from phenylalanine-cinnamic acid biosynthetic pathway. They appear in the form of their respective esters in many plants, spices and fruits but also in malting and brewing processes. In the metabolic activity of yeast, phenolcarboxylic acids are transformed, in part, to ethyl cinnamate and ferulic acid ethyl ester. Moreover, phenolcarboxylic acids undergo decarboxylation to produce phenols due to thermal stress during kilning, mashing or wort boiling. In contrast to bottom-fermenting brewing yeast, the top-fermenting yeast used to brew Bavarian-style wheat beer can modify ferulic acid through decarboxylation to produce 4-vinyl guaiacol, an important aroma component of Bavarian-style wheat beer.
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| p-coumaric acid | trans-ferulic acid |
Application/Purpose
Determination of coumaric acid and ferulic acid in wort and beer
Scope of Application
The method is suitable for wort and beer of any original gravity and alcohol content.
Principle
Reversed phase chromatography with UV detection