One of the things that consistently annoys me about foods marketed toward children are the ridiculous amounts of artificial coloring in them. This is especially offensive in light of research pointing to ways in which artificial colors exacerbate hyperactivity in children and can even be a contributing factor in the severity of symptoms in autistic children. Artificial colors are coal tar byproducts (as is saccharine, by the way), and really have no resemblance to actual foods. So what then to do about providing children with fun and interesting colors to eat? Why not take advantage of the wide range of fruits and vegetables that have natural colorants to produce colorful foods that are also more flavorful as a result of drawing their colors from real foods?
The cake pictured above has no artificial colors in its icing. It is iced with blueberry-flavored purple icing; black-currant flavored pink icing; and cocoa-flavored brown icing.
The easiest way to make naturally colored icing is to build the color into your butter. Follow my instructions for the black currant beurre blanc and let the resulting butter cool to room temperature, then use it to start the icing. The general formula for icing will be 4 cups of confectioners sugar per 1/2 lb of butter. 1/2 lb of butter is enough to ice a 10 x 15 layer cake. Make smaller quantities of icing for accent colors.
Here is a partial list of fruit-based colors that could be made this way:
Purple—blueberries and red wine
Pink—black currants and white wine; or strawberries and white wine, mixed with some plain butter
Red—strawberries and white wine
Green—kiwis and white wine
Yellow—saffron-infused white wine or turmeric whipped into the butter
Orange—combine red and yellow butters; or for a paler shade, use peaches.
Blue— This is not a natural color in food. It can, however, be achieved through chemistry: cook beets down with a base (such as baking soda). They (and the water they are cooked in) will turn blue. Reduce this water to almost nothing, refresh it with a half cup of white wine, then reduce again. Whip the butter into it per the beurre blanc instructions. It will not be a royal blue, but the hue can be adjusted by combining the resulting colored butter with other butter when making the icing.
The best part about using naturally-colored icing is the flavor that goes along with it. The purple icing was not just a visual component of this cake, but added a vibrant blueberry flavor that really was a fantastic addition to the final result.