Another issue, I understand, is that many older people not only lose their tastebuds, but also the ability to swallow the way they used to. This is especially marked in those with memory issues.

However, I've also read that a lot of the problem is simply that they are not getting enough hydration or nutrition. They settle for things that are cheap, or things that are easy, and this makes any problem they might have, worse.

I don't know how well it could work, since she's so used to eating a certain way, but getting her more water to drink and encouraging her to eat more nutrient-dense foods (seafood is a particularly good choice for this) might help, too.