Microbial Testing in Beer

When you open a beer, you expect it to be clean, fresh, and exactly how the brewer intended. But sometimes, unwanted microbes sneak into the process and even small amounts can ruin flavor, cause haze, or spoil shelf life.

At our laboratory, we offer microbiological testing and identification to help brewers catch contamination before it becomes a bigger problem. One of the most powerful tools we use is Raka Ray agar - a selective medium that helps us find beer-spoilage bacteria fast and accurately.

Why Microbial Testing Matters

Microbial contamination can cause:

Even in clean breweries, contamination can come from packaging lines, poor tank sanitation, hops, fruits, or barrels, infected yeast pitches, or faulty seals and valves.

What Is Raka Ray Agar?

Raka Ray (RR) agar is a special type of growth medium designed to detect and isolate anaerobic and facultative anaerobic beer-spoilage bacteria - especially Lactobacillus and Pediococcus, two of the most common culprits in contaminated beers.

Why we use it:

• Selective for beer-spoiling organisms
• Low pH and hop compounds simulate beer conditions
• Inhibits most non-relevant microbes (e.g. molds)
• Shows distinctive colony growth to aid identification

It's a proven method, recommended in MEBAK and other brewing microbiology guidelines.

What We Test For Using Raka Ray

We use Raka Ray to detect bacteria such as Lactobacillus brevis, Pediococcus damnosus, and other anaerobic/hop-tolerant spoilage species. Our lab can isolate colonies, incubate under brewing-relevant conditions, and identify morphology - so you know not just if there's contamination, but what kind, and how to respond.

When to Consider Microbial Testing

You should test for microbial presence as part of production routine, and if:

• Your beer develops unexpected off-flavors (buttery, sour, medicinal)
• You notice overcarbonation, haze, or secondary fermentation in package
• You're doing contract brewing and need peace of mind
• You plan to export or store beer for extended periods
• You're pitching harvested yeast or reusing cultures
• You're experimenting with non-pasteurized or barrel-aged beers

Testing is especially recommended after packaging line issues, cleaning failures, sour/funky flavors in otherwise clean styles, or dry hopping and fruit additions.

What You Get from Our Microbial Test

At our laboratory, we offer microbial testing using Raka Ray agar and other media - isolation, identification, and clear guidance on what was found and how to act on it.