Chapter 19

Beer Spoliage Organisms

Bacteria

For all practical purposes there are only seven common genera of bacterial contaminants in the brewery. These are divided into two categories according to their reaction to a differential staining procedure, the Gram stain. The Gram stain divides brewery bacteria as follows:

Gram-positive:

    lactic acid bacteria
      Lactobacillus spp.
      Pediococcus spp.

Gram-negative:

    acetic acid bacteria
      Acetobacter spp
      Acetomonas spp.
    Zymomonas spp.
    Enterobacteriaceae spp.
    Pectinatus spp.

Click on the following topics for more information on beer spoilage organisms.

Related Topics on Beer Spoilage Organisms

• Introduction Beer Spoilage Organisms
• Bacteria
• Wild Yeast
• Molds
• References