Iso-alpha and Alpha Acids in Beer - UV Vis Spectroscopy

This application note is based on the American Society of Brewing Chemists’ (ASBC) method of analysis of iso-alpha and alpha acids in Beer. For more information, please proceed to download the application note below.

What is the importance of acid in beer?

Acid in beer originates from the hops used in the brewing process. Alpha-acids contained in the hops are isomerized to from iso-alpha acids, which are responsible for the bitter taste of beer. The amount of iso-alpha acid in beer significantly effects the flavour of the final product and it is therefore monitered as part of the production process.

How is acid content in beer measured spectrophotometrically?

This UV Vis spectroscopy application determines the concentration of both iso-alpha and alpha acids in beer samples by an extraction method defined by the ASBC. Scans are performed at two distinct wavelengths in the UV region and their concentration is subsequently determined. Tips on laboratory technique are also provided to enhance the precision of results. UV Vis spectrophotometers along with LabX PC software from METTLER TOLEDO enable preset methods to be implemented into workflows for fast, reliable measurements and automatic results calculation with the guarantee of full data integrity compliance.