Homemade Yogurt: Culturing Bacteria
Project Overview: Yogurt is not made in a factory with machines; trillions of living bacteria make it. This project introduces you to real biotechnology, the same kind used to brew, ferment, and culture foods for thousands of years.
Materials Required:
2 cups milk
2 tablespoons plain yogurt with live active cultures
A small pot (for warming milk)
A clean glass jar with lid
A towel or insulated cooler
Instructions:
Warm the milk in a pot until it just starts to steam, then let it cool until warm to the touch, not hot.
Stir in the 2 tablespoons of plain yogurt, introducing the live bacterial culture into the milk.
Pour the mixture into your clean glass jar and seal it with the lid.
Wrap the jar in a towel and place it somewhere warm and undisturbed for 6 to 8 hours.
Refrigerate for at least an hour before tasting your creation.
Fun Fact: The tangy taste of yogurt comes from lactic acid, a substance the bacteria produce as they feast on the natural sugar in milk. You didn't just make yogurt in the kitchen; you ran a real fermentation lab.
