Some milk has been spilled on a book in my house. The book is an important one in our family, and my wife would like to minimize the damage.
Knowing how best to do this probably requires knowing what the cover is made of. I don’t know what the cover is made of, but I was hoping those here could help me figure out how to figure out what it is made of.
It’s not paper, it’s not leather, and it’s hard, not soft. That’s all I know.
Twenty questions, maybe? :dubious: 
-FrL-
Can you post a picture of it? Might arrive at an answer faster.
As for the milk:
Milk is largely water. Getting the book very dry very fast will likely solve most problems. I suggest blotting followed by personal time with a hair dryer for every page that is even slightly damp.
I’ll post a picture when I get a chance.
I didn’t mention that the milk was spilled sometime in the past couple of weeks, and somehow went unnoticed. My wife just picked up the book today and saw there was (what we are pretty sure is) a giant milk stain on the back of it.
-FrL-
It’s a “memory book” for our younger kid. My wife cried as though it wasn’t a book but the kid herself, and as though it weren’t milk but rather, death.
Making sure the milk doesn’t soak farther into the objects in the book, would be a logical step. A sheet of plastic between the contaminated and good pages, would stop further migrating. Putting some plain non inked absorbent toweling between the wet pages, for removal in a day or less may help dry it out better. Somebody else will have to give you ideas on removing the milk. I would keep the plastic between the good and milk stained stuff in the future so the milk can’t transfer to good pages over the years.
Is the milk dry already?
If yes, I doubt there is anything you can do to remove the milk that won’t damage it further. An expert in paper conservation may have suggestions, call your local museums for referrals.
If the stain is just on the back cover of the book, not affecting the pages, it should be feasible to cut out the pages from the cover binding, and glue the whole set of pages into a new cover.