Monday the wife opened as new bag of flour and inside was a load of very small grub/maggots. - We have had them before but were do they come from. This was a unopened packet and it was stored in a air tight plastic container so I am hoping they were in the flour to start with. I can't ever remember seeing them in anything else - not even pasta. Talking to a guy in supermarket and he bought a very large sack of dog food (breeder) and when he opened it it was riddled and they had spread all round his pantry - Dog food maker paid for the clean up. Any ideas - I could google it but wanted real live reports.