What is the ruling regarding blowing on food to cool it?

There is a hadith in Sahih Bukhari where the Prophet prohibited blowing over food and drink. However, it's important to understand the reason for the hadith. It's not just for any particular reason. If, as the scholars mention, that is a concern, you may spread germs over the food, then yes, this is when it would not be allowed. However, if you're doing it, let's say, to cool down your food, let's say you're giving it to your child and it's a bit too hot and you're blowing it to cool it down, then that's fine. The main reason for the prohibition, as many of the scholars of hadith say, is if there is a concern that it may spread germs.