ELI5: Explain Like I'm 5

Food testing strips

Food testing strips are like tiny strips that have special chemical paper on them. You can use them to test the food you have in your kitchen. For example, if you have a bottle of milk, you can use the strip to touch the milk. The paper will change color and tell you if the milk has gone bad. The strip is like a special type of paper that can tell you if something is safe to eat.