Mrs. Pfahnl’s Bio A Lab: Fermentation 1 Yogurt
Fermentation does not require Oxygen. There are two types of fermentation: Lactic acid and alcohol. Yogurt making is similar to our muscle during excise which produces lactic acid.
Purpose: Observe changes during milk fermentation process.
Materials:
1. Milk (Any kind. cow milk is the cheapest. Other milk will work.)
2. Yogurt (It is the starter. Needs to be the same milk yogurt as the above. Greek Yogurt may be ideal for cow milk.)
3. Table sugar (Crystal sugar is the easiest to dissolve.)
4. Clean cups (Dishwasher cleaned is ideal.)
5. Measure cup and spoon
Procedures:
1. Label 4 cups 1-4;
2. Add half cup of milk to each cup;
3. Cup 1, no sugar;
4. Cup 2, 1 tsp sugar;
5. Cup 3, 1 tbsp sugar;
6. Cup 4, 2 tbsp sugar;
7. Add ½ tsp yogurt to each cup and mix well;
8. Put the cups in oven and turn on the light;
9. Observe in 12 h, 24 h
Four clean glass jars (dishwasher cleaned).
Clean 1 teaspoon ( boiling water cleaned)
Add 1 teaspoon sugar in jar 2.
One clean tablespoon (boiling water cleaned)
Add 1 tablespoon sugar in jar 3. Then 2 tablespoons sugar in jar 4.
Half cup of milk.
Add milk to each jar.
Milk in all jars.
Use a clean spoon to mix sugar into milk.
Fresh Greek yogurt.
Add ½ teaspoon yogurt into each jar.
Mix with clean spoon.
Put in oven.
Keep oven lights on.
Result:
1. Pictures 34%;
2. Data 33%;
3. Presentation 33%.
Links:
Lactose and yogurt: https://pubmed.ncbi.nlm.nih.gov/1957819/
Yogurt and gut health https://www.sciencedirect.com/science/article/pii/B9780128051344000237
Yogurt story https://www.npr.org/sections/thesalt/2015/07/15/391927036/hey-yogurt-maker-whered-you-get-those-microbes#:~:text=By%20law%2C%20anything%20called%20%22yogurt,well%20as%20fruit%20and%20flavorings.)
Yogurt 100 year review https://pubmed.ncbi.nlm.nih.gov/29153184/
Anti cancer properties of yogurt https://pubmed.ncbi.nlm.nih.gov/31643163/
Yogurt is a Low glycemic index food https://pubmed.ncbi.nlm.nih.gov/28615381/