ASBC Methods of Analysis - Wort-21: Thiobarbituric Acid Index
ASBC Methods of Analysis
Thiobarbituric Acid Index
The thiobarbituric acid index method is applicable to both beer and wort. It is a colorimetric assay based on the absorbance of reaction products of thiobarbituric acid with lipid peroxidation products in an acidic medium. Values from the analysis can be used to estimate the level of heat stress a product has undergone during processing (low values = low thermal stress; high values = high thermal stress). By quantifying the effects of heat on wort and beer, a brewer can make adjustments to the process upstream to reduce the level of heat to which the product is exposed during production. Reducing the level of heat stress during beer production is believed to have a positive effect on the flavor stability of the beer produced. This method is particularly useful for brewers who are increasing production, either by brewing at a new location or using different equipment in the brewhouse, and want to maintain consistency of the product.