CWS, one of the good thing about dementia or Alzheimer's (if there is such a good thing) is that the patient may not remember today and yesterday, but they do remember yesteryear. This might just be the best time to ask her about your grandmother's recipes.
There is one patient at Winthrop that talks about her children as if they were going off to school today. She wants to make sure they have their lunch and are dressed warm. Yet when her kids come to see her, she has no idea who they are. She thinks they are staff members checking up on her. Her kids are all in their 50's.