Milk Stout is a fancy name for a sweet stout. It is typically sweetened with lactose, which is an unfermentable sugar from milk solids. The yeast can't eat it and turn it into alcohol, so the sugars from the lactose stays in the beer after complete fermentation.
Typical commercial example is Mackeson's XXX. I'm not a big fan of it but a guy had a coffee-toffee milk stout at the NHBC and it was amazing. Breakfast beer. Dump that on pancakes (or ice cream) and you've got something very nice.
Ingredients and recipe are TOP SECRET at this time. Sam and I are having a little friendly competition to see who can get closer to the coffee-toffee one (we called it LPR--liquid panty remover) we had in Baltimore. We haven't set a brew date yet but it will be soon, because we have to have it ready by our September (or October, can't remember) brew club meeting.
I'll post my version of the recipe when I win.
I was planning on brewing a milk stout and bought the milk solids for it, but i just kept putting it off and now its been over two months since i bought the ingredients. will they have gone bad by now?
Can i still use the milk solids? it's in a vacuum sealed bag.