Now, she won't touch the new food, at all. I even "on purpose" forgot to fill her bowl with the old cat food Friday. So, by Saturday morning there was a lot of meowing comming from the kitchen. Yep. Old food gone. New food untouched. I didn't know what to do so I just filled a bowl with old food again.
Again Cats can be more challenging than dogs. Mixing the food the best way start 80/20 then after a few days move to 40/60 etc. It may take a few weeks, it can be a slow process for some pets. Don't give up.