I roast white coffee, you are served a latte. White coffee is coffee roasted to a degree of almost tannish/golden and smelling like peanuts. You can make a latte or anyothe espresso drink with white coffee, but the drink will not thave the normal coffee taste. Because the bean(s) are so under-roasted that the " roastedness" isn't really presented.
I hope this helps ( BTW most people who've tasted a white coffee/white mocha -love it)