Hi all, Im not very knowledgable with food, and couldn't find much when I googled. I've got a sirloin steak here that has been in the fridge for a 3 days and the sell by date is the 24th of July. So it should be fine, but I was slightly concerned to see patches of gray/browness on the steak. Does this mean the meat has gone off? I smelt a bit of the meat that I cut off and threw away which had a bit of brown on and it smelt fine so it didn't seem to have gone off. If it hasn't gone off, then what is this colour? Cheers!