what do you feed silkies before a show and for how long.

[bargain]

I'm thinking of trying to see if our local mill canmake the following homemade organic feed.
Corn, 2 parts whole or cracked
Wheat, 3 or 4 parts
Oats, 1 part
Sunflower seeds, 1 part hulled, 2 parts shelled
Green Lentils, 1 part
Split Peas, 1 part
Barley, 1 part
Millet, 1 part
Flax, 1 part
Seaweed or Kelp Meal, ½ part,

I'm concerned that the corn, will turn our white feathers yello what do you think?