Homemade yogurt

Yogurt is a food produced by bacterial fermentation of milk. I experimented fermenting my own yogurt at home.

Ingredients:

Yogurt - prefer plain yogurt. 1 pack is about 1 cup. The yogurt needs to "Contain active yogurt cultures"
Milk - 5 cups
Sugar - optional, add whatever to your taste. I added about 3 TBSP

Steps:

1. Set yogurt out in room temperature.
2. Boiling all parts that will touch the yogurt mixture to sterilize them - that include the container , any teaspoon or spatula used for scoping and mixing.
3. Boiling milk in sauce pan and add sugar. Let milk cool to 113°F (45°C), then mix the yogurt with milk. Stir well.

4. Put the mixture in sealed container and keep it warm. You can wrap it with blanket. I put it in a Thermos. Inside the Thermos, I put in some hot water to keep it warm.

5. Overnight, the yogurt will solidify. The longer you keep it warm, the thicker the yogurt will be.

6. When you are satisfied with the thickness, put the yogurt in refrigerator to stop the fermentation.