why can’t you mix old and new flour?

Question

I just read somewhere that you shouldn’t mix old and new flour, but can’t find any websites that explain why you shouldn’t do this. Does anybody know?

In: 42

Answer 1

Raw flour can harbor microorganisms that can make you sick, as well as things like insects and insect eggs and larvae. The longer it sits unused, the more likely it is to have more of these things, so if you mix new flour with old flour you’re introducing more of those bad things to the new flour and causing it to go bad much sooner.