These seeds have a nutty-tasting flavor and are mostly used in baking. These can be used in bread, cakes, pastries, rolls, and cookies. Refrigerate or freeze poppy seeds to maintain freshness. There is blue-black in color. Poppy Seeds are small, nutty-tasting seeds, mostly used in baked goods for color, texture and mild, floral and earthy flavor. The nutty flavor of blue poppy seed is fantastic when used for muffins, cakes, bread, or cookies. Cooked in milk, these seeds turn a gorgeous shade of blue and so does the milk.