Not unless merely loading the save file without even saving it still changes it somehow (God, I hope not.)
Merely loading doesn't change saved game.
And unless something can preemptively change the food value for Barren planets somehow so that it's adjusted to take effect upon Terraforming then I don't understand why I'd keep seeing it, I definitely haven't been loading 1.31 since then.
You should have uploaded saved game, otherwise it's guesswork. I presume that you (despite saying it's unlikely) have somehow cycled formats, so classic->1.50 transformation has been applied. That means that all planets have base food doubled. If that's the case it can be fixed in the following steps:
1. In launcher select Edit->Scripts->MAIN2.LUA, file should open in editor.
2. Delete all contents.
3. Paste the following code:
pp = get_planets()
for i,p in pairs(pp) do
p.food_base = p.food_base / 2
4. Save the file.
5. Load your game and in main screen press Alt+LUA (hold alt and type lua, as if a cheat). It should say "Scripting full access enabled".
6. Press 2, should say "it works". Check your planets food output, should become correct.
7. Press Alt+LUA again to disable unsafe mode.
- This will mark game as if cheat has been used, so no hall of fame for you.
- If you played for some turns since base food has been corrupted, then newly built artificial planets may have correct food so it will be halved and will become incorrect. In the same way if you built soils since corruption, you have incorrect base mixed with correct soils bonus, which can't be fixed easily.
Btw, if you figure out how you arrived at such save, please report it. It may just be that there's a bug in corion2 or in patch. Also, can you describe what you change with corion2? It may provide a clue to what happened.