When this culture is kept in the right conditions, it will continue to grow and provide leavening for many years.
en.wikipedia.org Almost all quick breads have the same basic ingredients: flour, leavening, eggs, fat (butter, margarine, shortening, or oil), and liquid such as milk.
en.wikipedia.org One variation involves leavening the dough and not flattening up the coil into a pancake.
en.wikipedia.org In addition to flour, doughnuts may also include such ingredients as water, leavening, eggs, milk, sugar, oil/shortening, natural flavors and/or artificial flavors.
en.wikipedia.org