(KERO) — Humans have been making cheese for thousands of years. Although cheese was most likely discovered by accident, a lot of science goes into modern cheese making. In this edition of Science Sundays, we’ll be making what is probably the most basic type of cheese; cream cheese. 

Items needed: - Half a gallon of whole milk 

• Juice of one lemon
• One large pot 
• A heat source, like a stove or hot plate 
• Colander 
• Cheesecloth 
• Blender 
• 1/4 tsp salt (optional) 
• seasonings (optional)

Safety Precautions: Hot liquids can cause burns. Parental supervision is recommended. 

Procedure: 

Step One: Heat the milk in a large pot until it begins simmer. 

Step Two: Turn off the heat, add the lemon juice and stir for at least two minutes.

This is where the science comes in! As you stir you’ll notice the milk will begin to change, and solids will begin to form. We call those solids curd, and that’s what we’ll use to make the cheese. 

The reason why the curd forms is something called Protein Denaturing. This means we change the structure of the proteins in the milk. The protein, called casein, is wound up tight like a ball in its natural form. When we add heat and an acid like lemon juices the protein unwinds into a long strand. Those strands then clump together, forming the curd. 

Step Three: Strain the mixture through a colander and cheesecloth. 

Step Four: Rinse the curd with cold water until cool. 

Step Five: Squeeze the curd in the cheesecloth to remove excess moisture 

Step Six: Add salt and seasonings if desired, and blend until smooth and enjoy!