Are you joking? Rats can eat almost anything. I think there might be a couple things they shouldn't have. I feed mine all sorts of scraps, and they like eggs, bread, pasta(cooked pasta!!!!), vegetables, crackers, you name it. I've found very few things they don't like. Given in moderation of course, feeding them nothing but potatoes won't be good for them obviously.
The other day I gave them stale powdered sugar donuts. They liked those too.
I love to offer them neat things to keep them happy. Dried fruit is good too, but I think the big thing with mine so far is cooker pasta. Whatever is on sale, buy it, cook it, little olive oil on it, and store it int he fridge. Give them some, you will be amazed.
Wolfy