It seems that whomever I am around, there is a difference with something. Sometimes if I am at my aunt's house, my farts smell really bad. Today my grandmother is over, and I am noticing my farts are really, really foul smelling. I am sure it could be from all the food I have eaten in the past 2 days, but this is just quite weird. The environment you are in will change the odor of your flatulences.