I have two ideas for today and they both have to do with fat.

First, did anyone read the Weekend Fun for making cheese? One of the cautions was to watch out because the milk can suddenly bubble up and over the pan when heating. I have had that experience a couple of times. I began to wonder why milk would act this way whereas water does not.

The answer goes back to the fact that oil and fat float on water. While heating, the milk fat forms a layer at the surface, repressing the activity of the liquid underneath. At boiling temperatures the fat layer splits all of a sudden, allowing the liquid underneath to roil up violently. Soymilk, with added oils, can have the same reaction.

How would you test this idea? I would suggest seeing whether heating nonfat milk had the same reaction. Then add oil to nonfat milk and do the test again. What happens? Do you have any other ideas?

The next part has to do with another kind of fat. Take a look at this article on how the species of bacteria in your gut during early childhood may determine whether you are obese later on.

I knew a little about how important gut microorganisms are in other creatures. My favorite critters, the insects, have many bacteria and/or protozoa inside them performing all sorts of roles. For example, termites can’t really digest the wood they eat. They carry tiny organisms inside that are able to digest wood. Without them, the termites would starve.

Obviously we have a lot to learn about our own relationships with microorganisms.

Science News for Kids is an electronic newsletter available for anyone. Just visit the page and sign up. It has been uniformly high quality over the past year and contains useful, current and interesting information.