Used in microbiology for biochemical testing to differentiate Gram-negative bacteria, particularly Enterobacteriaceae. Supports the methyl red test to detect mixed acid fermentation and the Voges-Proskauer test to identify acetoin production. Helps distinguish between bacterial species such as Escherichia coli, which is methyl red positive, and Enterobacter aerogenes, which is Voges-Proskauer positive. The broth allows both tests to be performed from a single inoculated culture after incubation, making it efficient for bacterial identification in clinical and environmental labs.