Neat sour beer video from ACS

Via Laboratory Equipment:

...“Scientists are very interested in beer and especially sours because they are such complicated systems,” says Teresa L. Longin, one of the project’s principal investigators. “There have been several prior studies of the components in finished sour beers. What makes our study different is that we’ve been able to get samples of beer in progress from many different batches.” Their findings could help brewers make better products. 

Longin was drawn into the study by her husband and co-PI, David P. Soulsby, and both are at the University of Redlands. When Soulsby began the project a couple of years ago, he reached out to Bryan Doty, a master brewer at nearby Sour Cellars. Doty was eager to learn what was going on in his beer and has provided a series of samples from the same barrels as the beer has aged. 

Soulsby and undergraduate student Alexis Cooper examined each sample using NMR spectroscopy coupled with a new analysis method for quantitating the data. They used this approach to track the levels of acetic acid, the main component of vinegar; lactic acid, which gives sourdough bread its distinctive taste; and succinic acid, which is found in broccoli, rhubarb and meat extracts. They found that each acid stabilized at similar concentrations in the different batches, though some batches had greater variability.

I'm not really a sours guy myself, but it's interesting to see the various compounds that can derive from the fermentation...