Mikie, first let me welcome you to Pet Talk., and congratulations on adopting an older kitty from the HS.
In regards to your Tuffy scratching beside his food plate. Nothing to worry about, it is a cat thing. I've had plenty of cats who have done this. To me it seemed they did this with the thought,
"I'll cover this and get back to it later".
Enjoy your new furbaby who will give you nothing but unconditional love.