This looks grand. I don’t trust anything that is stored at room temperature and shouldn’t be. What do they add to it to preserve it? Your way is much better! (Although I have a fondness for various cold cuts – but at least they need to be refrigerated.
I eat tons of canned tuna… I wonder if your professor was referring to those as well. I’ve heard they’re not great, but they’re just so convenient!
Making your own sandwich meat shows commitment and dedication! good job!