Alicyclobacillus

Alicyclobacillus is a genus of bacteria in the family Alicyclobacillaceae. They are acidophilic, thermophilic, and produce endospores. The genus was first described in 1987, and currently includes 27 species.

Characteristics

Alicyclobacillus species are Gram-positive, rod-shaped bacteria. They are thermophilic, meaning they thrive at high temperatures, and acidophilic, meaning they prefer acidic environments. They are also aerobic, requiring oxygen to grow.

One of the defining characteristics of Alicyclobacillus is their ability to form endospores. Endospores are a type of dormant, tough, and non-reproductive structure produced by certain bacteria. They are resistant to extreme conditions that would normally kill the bacteria, such as heat, radiation, and chemicals.

Species

There are currently 27 recognized species in the Alicyclobacillus genus. Some of the most well-known include:

• Alicyclobacillus acidocaldarius
• Alicyclobacillus acidoterrestris
• Alicyclobacillus herbarius
• Alicyclobacillus pohliae

Significance

Alicyclobacillus species are of particular interest in the food industry. They are known to cause spoilage in fruit juices, particularly apple and orange juice, due to their ability to survive pasteurization. The presence of Alicyclobacillus in juice products can lead to off-flavors and odors, making the product unsuitable for consumption.

Detection and Control

Detection of Alicyclobacillus in food products is typically done through microbiological testing. Control measures include heat treatment, acidification, and the use of preservatives. However, due to the bacteria's ability to form endospores, these measures are not always effective.

See Also

• Bacteria
• Endospore
• Food spoilage