Just checked this in 1.1.1. The game says "You feel strong" after "You are done eating...", irrespective of whether 1 St is gained or not.

I remember this happening for one of my PCs in prerelease 11... I was thinking it could have been a frost giant jarl, but then again it might have been a fire giant king. I just remember expecting to see a "your muscles feel like steel!" message or something, but was surprised to see no message at all (besides "you are done eating the -foo- corpse.").

Messages (like "Tastes good.") only exist for some corpses. You might miss messages like "You feel strong", they are now shown only if something happened to your stats, see issue 728 for the bugfix.

Like faradan, I also thought eating anything gives some sort of message whether or not it confers a special effect.

A *few* examples:
()Eating an orc butcher or dark orc gives the message "Your muscles bulge!" if +1 St is granted, AND "Tastes like pork... old/bloody pork." in either case
()Eating a (regular) frost giant gives the message "Your muscles feel like steel!" if +1 St is granted, AND "Frozen meat." in either case
()Eating a fomorian giant gives the message "You grow a wart!" if -1 Ap is granted, AND "Yikes! Slimy meat" in either case
()If teleporting powers are not granted after eating a pixie (archer), a message is still received about the texture/taste of the food: "Hey! This tastes like candy!"

and so on.
Even if the new behavior *is* intentional for fire giant kings and frost giant jarls because of that bugfix, it still seems very out of place to not still receive some message on the taste/texture of food after eating it even in the absence of an additional effect.
Maybe, instead of a bug report, this could have been considered a feature request for some sort of message to be generated for eating such monsters even if the +1 St is not granted?
For example: "You feel an enormous fire in your throat!" for eating fire giant kings or "You feel an enormous chill down your spine!" for eating frost giant jarls

I found some examples where a "food message" was missing too (e.g. Hydra or Giant Centipede), so I thought it was intentional. But I guess we should add a message for the monsters from the bugfix. Re-opened and assigned to Thomas.

Fixed.