Every time my husband eats the gravy, he has stomach issues and gets diahrrea. I don't have any problems when I eat it.

He does not have any issues with anyone else's gravy either. Just mine. I use the same sausage his mom has used his whole life. I use the standard recipe. Brown sausage, flour, milk, salt and pepper. There's hardly any grease in the pan after I brown the sausage, so I don't usually drain it, but I have tried draining it and soaking it all up before adding the flour, and it still made him sick.

He has tried my gravy about 4 times over the last 8 years we have been together, and no matter what I do, he has this problem.

What could it be?