If you make a book only out of games that were won by white, you get a book that contains no moves for black. Because the weights of those moves would be 0, as no points were scored with them. So all you have to do is delete the black wins with the openings where you don't want your engine to play black, etc, and then make the book.
I have only made a book with Polyglot once, but have forgotten how. Note that WinBoard/XBoard also has a Save Games as Book function, but it is still a bit experimental, and there might be limitations to the size of the book. I don't know how large your collection of games is.