Most healthy cats have good immune systems, and in my opinion wouldn't be harmed by food sitting out for an hour. Neither of my two have ever been negatively affected by not having their food immediately refrigerated. In nature, they'd be exposed to a lot more germs than they are inside, and generally their systems can handle it as long as you aren't taking it to extremes.
That said, it sounds like maybe the servings you're giving her are a bit overwhelming for her. If I were you, I would try feeding her the same amount of food but spreading it out over a couple of smaller meals, to see if that helps her manage it better.
The Boys: Maisie, Zephyr, and Cullen.