Temperature Viability

• Historically, L. acidophilus has been studied by the dairy industry for its use in food production. In 1931, a scientific study was published by the American Dairy Science Association that stated L. Acidophilus bacteria is preserved in cultures stored in refrigerated conditions, from 32 degrees to 48 degrees Fahrenheit. Cultures stored at higher temperatures, 99 degrees Fahrenheit, saw a significant decrease in organisms.
  
  

Health Benefits

• Probiotics are often sold as a health supplement with claims of boosting the immune system and helping various ailments. The American-Eurasian Journal of Scientific Research published a study in 2011 which experimented on the use of L. acidophilus in rainbow trout. The study found that higher doses of L. acidophilus resulted in greater red blood cell counts, white blood cell counts, hemoglobin and growth performance. The subjects which had higher doses of L. acidophilus also showed a lower mortality rate than the control group.
  
  

Antibiotic Acquired Diarrhea

• Whenever a person takes antibiotics to help cure a bacterial infection, the antibiotics often attack and destroy all bacteria in the body. This includes the helpful L. acidophilus, which lives in the intestines and the mouth. The loss of intestinal bacteria can result in diarrhea for the patient. Some sources suggest taking probiotics to help combat this form of diarrhea. Various studies have been done on this subject, and specific experiments can be done in the classroom or laboratory to test the outcome of probiotics on antibiotic acquired diarrhea.
  
  

Oral Hygiene

• Because L. acidophilus lives in the human mouth, it can cause tooth decay if it grows out of control. A classroom experiment can be conducted to show the presence and growth of L. acidophilus in the mouth. Use toothpicks to take samples of material from between the teeth. To determine the rate of growth, start with a mouth that has just been brushed. Take additional samples at later times, and even after eating different types of food. This can determine bacteria growth in the mouth and what conditions increase that growth.