I make my own buttercream, 1/2 shortening and 1/2 butter. If I need a white color, I use clear vanilla. It starts off pretty white, but it tends to darken to an ivory color. Any suggestions on how to prevent that? Should I just use all shortening?

I think the only way to get a pure white icing is to use only shortening.

Wilton makes something called an icing whitener. I have never used it, but I have read good things about it. I see it at Michaels. HTH!

I use it and I think it works well.

I use only shortening in my icing, it turns out white not ivory.

I use the Wilton Icing Whitener stuff also. Amazing how just a little bit can make your 1/2 butter buttercream turn BRIGHT white. It's so clean and pretty without sacrificing taste or texture!

I used it tonight to paint a gumpaste airplane white. Didn't want it to look dull... Just added a little super pearl dust, a couple drops of rum, and painted away. Amazing!

I always advised my brides that my icing would not be pure white. I had 'white' walls in my shop and pointed out that the color of the icing would be about that. There was only 1 person who was not happy upon delivery . The rented linens were sooooooo BLUE white I could not believe it. No wonder they were not happy.

I'll have to try the icing whitener - I actually have some, but hadn't thought to use it!