Raka-Ray No. 3 Medium is recommended for the isolation of lactic acid bacteria encountered in beer and the brewing process.

• Dehydrated appearance: beige, free-flowing, homogeneous
• Prepared appearance: medium to dark amber, clear to slightly opalescent
• pH: 5.4±0.2 (at 25 °C)

It also suppresses the growth of non-lactic acid, facultative bacteria, such as Aerobacter aerogenes and Flavobacterium proteus that are often associated with lactic beer spoilage organisms.

This medium is also recommended by the ‘European Brewing Congress Analytical Microbiologica’ for enumeration of lactobacilli and pediococci.