-Corn can contain mold, which will kill your rats quickly(or slowly depending on the mold and amount ingested)
-Alfalfa is NOT digestible by rats.
-Sunflower seeds, unless they are the black oil type, are incredibly fatty and should only be given as a treat.
Cooked peanuts are fine as are the soybeans, oats, millet and milo. Although the last two are pretty small and they probably won't eat it.

So all in all, it's junk and you can easily just MAKE your own and it will be less expensive.

1-2 bags of tri-color pasta, 1 large container of long-cooking oatmeal(not the quick), box of puffed rice, box of crispy rice, box of puffed wheat, box of barley, box of Kashi cereal if you choose, small bag of black oil sunflower seeds, 1 bag of in-shell, cooked, unsalted peanuts, and a small amount of HIGH QUALITY senior dog food. No store crap like Doggy Bag, BLEH. Wellness is good, Innova is good, Doctors Foster & Smith senior dog food is good(target has it). No higher than 18% protein.

Mix all this together and voila, a much healthier mix without all the FILLERS. Corn is a filler and just contains sugar, plus the mold issue. Alfalfa is just a filler to rats. If we were talking rabbits, that's different. Striped sunflower seeds are only good as a treat, way too much fat in them.