Yes. It's not as good as actual formulated yeast nutrients, but it is an easy option. It's not typically necessary in beer fermentation, however. It's more commonly added to wine or mead recipes as a nutrient. In those cases, it's typically boiled separately in a small amount of water and added to the must.
I've heard of using that with DAP and zinc as a homebrewed yeast energizer/nute. Could use bulk-bin brewers' yeast as well, but in the quantities we're using, it likely doesn't matter....
Nice, ran out of fermex on my last batch and have lazy and cheap so I haven't replaced it yet. I've got two packages and thought one would help out some. Thanks for the response
That's interesting. I've got some expired Munton's that came with my first kit. I'll give it a try in my next batch instead of my regular yeast nutrient.