If the white areas are not quite as white as they should be, you can boost them using the Selective Color adjustment in Photoshop
Load up the Selective Color adjustment from the Layer>New Adjustment Layer menu. Change the Colors option to Whites and then reduce the Black slider down towards -100% until the whites are whiter.
This means that the exposure of the image goes mostly unaffected, and you don’t end up with bleached highlights – like you would if the Levels adjustment was used, for example.
Also, change the Colors option to Neutrals and reduce the Black slider. This will help lighten the white areas as well.