It's the same with Polee. I've tried dog shampoo specifically for white dogs but the yellow tint soon returns. I think I'll start telling people her colour is isabella or that she an albino husky just to see the look on their faces (lol)
I hadn't heard of this colour until you mentioned it but a search on the net found the following source of information regarding the colour isabella:
isabella
(iz-uh-BELL-uh)
Grayish-yellow; light buff in color.
It was 1601, and the Austrian Archduke Albert was determined to capture Ostend, a coastal city in northern Belgium.
The story goes that the archduke's wife, Isabella, came up with a most unusual motivational technique to assist her husband's military efforts: She declared that she wouldn't remove her underwear -- even on laundry day -- until he took the city. Unfortunately for the couple, Ostend's defenders held out for three long years before falling to invaders.
Thus the color name isabella and its offspring, isabelline, came to describe anything having, well, the color of underwear subjected to over-wear. That's the story, anyway.
Alas, however, this proposed etymology doesn't quite wash with the Oxford English Dictionary, which points out that the first recorded use of isabella to describe such a color occurred in 1600, referring to "one rounde gowne of Isabella-colour satten . . . set with silver spangles." That's fully one year before the siege of Ostend began, which sort of shoots holes in the underwear theory.
It may be that the real story behind this word will remain lost forever in the mists of history. But at any rate, isabella and isabelline often describe the color of various animals (such as the bird called an isabelline shrike, and the isabelline bear, a yellowish-brown bear of the Himalayas, and the isabella moth), as well as fruits, such as the Isabella peach.
"Really, Marvin, we must do something about this depressing apartment of yours, and we should start by getting rid of this dreadful isabella wallpaper."
Like Eddie when bathed Polee is pure white but does have a yellow / beige tint when dirty