Carbohydrates are the real feed stock in corn (maize) used to make ethanol. Left over are "distillers grains" https://en.wikipedia.org/wiki/Distillers_grains as in "protein, fibre, fat" which is used as animal fodder, especially for ruminants who can digest the fiber.

The real total loss is in biodiesel made from vegetable fats. I can't remember the numbers now, but I read the German use of them is a substantial fraction of the sunflower oil that's no longer available from the Ukraine.