Are you exercising him, outside of the yard? Also what commands does he know? Will he respond to your roommate?
To work with a dog who is having issues with food aggression, you need the animal to be well exercised. *Very Tired. Not from just normal home life and/or going out in the yard.
Next step is have a leash on your dog (prong or at minimal choke chain) and have either you or your roommate hold the leash, while dog is with both in kitchen. Set the dog up for failure, drop items on the floor. When dog goes after it, pop collar and say no. When the dog sits/lays and behaves properly you can give it a treat. Make the dog eat it from your hands.
All feeding should happen from your hands, no bowl. If the dog becomes stiff, growls or eye balls you. It doesn't eat. Walk away and put food up. Dogs can go days without eating, without it damaging organs or growth spurts. I highly recommend feeding only from your hands, even meat until the dog eats properly from you without any signs of aggression.
To do the above you have to be willing to walk away, let your dog be hungry. If not, then don't even consider doing it. Because it will not serve any purpose.
The dog needs to believe that it will only eat from your hands, at first it will refuse to do so properly. But as hunger sets in, the dog will become humble and submit in order to eat.
I can give you a few other steps, but above should be enough. Set your dog up for failure, train it accordingly and use equipment while doing so (leash/collar), don't feed in kennel at first. Slowly work your way to that point. Where you can sit inside and the dog politely eats with you.