The separation of the anions was done via ion exclusion on the Metrosep organic Acids column. Conductivity detection after reversed suppression was applied for the quantification.
A drop in the acidity of sourdough during the fermentation process has an important impact on the biochemical changes in the carbohydrate and protein structures.
The drop in pH value caused by organic acids doesn’t only affects the taste and smell but also to physical properties such as the viscoelastic behaviour of the dough. In order to get a good understanding about the acidification process of the sourdough and partial acidification of the bread dough, it’s important to quantify the acids that are responsible for the pH drop.
Certain acids will contribute stronger to the acidification than others due to the differences in the pKa values. (Refer to table below).
This MEP Application provided for free download below explains the determination of organic anions in bread dough. The organic acids were extracted by using a mixture of acetonitrile and water. The acetonitrile was added to stop the biological processes in the fermentation samples.
The separation of the anions was done via ion exclusion on the Metrosep Organic Acids column and the 930 IC Flex