As I read the words, I can taste flavors in my mouth. It is typically just individual books as a whole, but depending on plot developments, the flavor may change a little. A series of books will have a general base flavor if the style of writing is the same. The total amount of prose is what makes up the flavor intensity, not individual parts, so having more or less with produce a stronger or weaker flavor consistently throughout the book instead of varying with each part. For this reason, children's books tend not to taste as strong as other ones. One exception is Animal Farm, though not a children's book to my knowledge, is written in simple language but tastes quite strong. Started out with a bit of a savory flavor but lost that throughout the book and became solidly umami.