| Bacillus | - gram positive, rod-shaped bacteria
- straight cells; motile or nonmotile
- aerobic or facultatively anaerobic
- most are mesophiles
- one endospore per cell; spores very heat resistant |
| Bacillus examples | - Bacillus cereus and B. anthracis: pathogens - some B. cereus are psychotrophic, can grow at fridge temps - B. coagulans and B. stearothermophilus: cause food spoilage in canned foods - B. subtilis: produce enzymes for food bioprocessing (ex. amylase for starch degradation) |
| Alicyclobacillus | - gram positive, rod-shaped bacteria
- forms spores
- non-motile, strictly aerobic
- isolated from soil, acidic, juices, orchards, and juice production equipment
- spoils fruit juices |
| Alicyclobacillus example | Alicyclobacillus acidoterrestris - thermo-acidophilic - growth temp: 20-55 C - pH range: 2-6 |
| Clostridium | - gram positive, rod-shaped bacteria
- motile or non motile rods
- anaerobic: some species very oxygen sensitive
- thermophilic, mesophilic, and psychrotrophic strains
- endospore formed at one end of cell
- in soil, marine sediments, sewage, decaying vegetation, animal and plant products |
| Clostridium examples | - foodborne pathogens: Clostridium botulinum, C. perfringens - food spoilage organsims: C. saccharolyticum, C. tyrobutyricum, C. laramine |
