Turning cream into a stick of butter involves some complex chemistry, crystallization, and (traditionally) fermentation. Learn more -- plus the difference between sweet cream, cultured, and European butters -- in today's episode of BrainStuff.

How Does Myasthenia Gravis Work?
13:47

What Is It Like In Our Asteroid Belt?
12:53

BrainStuff Classics: How Did Fish & Chips Become England's National Dish?
07:17