The most significant difference between white and purple eggplant is color and size. The white eggplant is smaller, and it is also thicker, less bitter, and creamier. Another difference between the two eggplants is in the seeds. The white eggplants come with more seeds, and the purple eggplant has thinner skin.
When it comes to cooking, the skin of the white eggplant has to be peeled off. It is a step that is not necessary when cooking purple eggplant. The white eggplants are better baked, steamed, or even fried because of their tough skin. For eggplant parmigiana, purple would be the best choice because of the thinner skin and less seeds.