ELi5: Why can’t you boil a sponge to sanitize it?

Question

Googling repeatedly tells you to just buy a new kitchen sponge, never boil them because it doesn’t work. But why wouldn’t it clean them?

In: Biology

Answer 1

Boiling or microwaving will KILL the bacteria. What it won’t do is REMOVE the dead bacteria. That means there is dead biological material that’s just food for more bacteria. The more you sanitize the sponge, the faster more new bacteria will grow… ELI5-when you kill bacteria it becomes bacteria food.

Edit: Wow. So. Heat, UV, bleach & desiccation(alcohol/sanitizer) can all kill bacteria. But there is no practical way to clean the material out of the deep pores of a sponge without destroying it. Nothing is as good as a clean sponge.

A short video of a single celled organism dying that demonstrates this concept:

DISCLAIMER: I am by no means a subject matter expert nor do I represent big sponge corp.