If this is a morning arrival in FRA, I would be very concerned. Very likely you will be parked at a remote stand, and have to bus to the Terminal, then clear Passport check, with hundreds of your new best friends. And run to Terminal B, which may involve a bus shuttle to your plane.

That being said, we have cleared a 40 minute connection...just barely. But that was a mid afternoon landing, and we got a gate. We were in Business, and we were literally the second or third people at Passport check, and the last to board our connecting flight to CPH. And our bag even made it!