Businesses in the manufacture of breakfast cereals turn grains and other ingredients into foods intended to be eaten at breakfast or as snacks. Products can include oat porridge, muesli, granola, toasted or puffed cereals, flakes and shaped or extruded cereal pieces. Common ingredients include oats, wheat, maize, rice and barley, alongside dried fruit, nuts, seeds, cocoa, honey or flavourings. Recipes and production methods vary according to the texture, taste and nutritional characteristics of the finished product. Manufacturing may involve cleaning and milling grains, mixing ingredients, cooking or steaming, rolling, puffing, baking, toasting and drying. Finished cereals are generally cooled and packed into bags, cartons or other food-grade packaging for retail or food-service use. Some manufacturers also provide contract production, recipe development or packing for other food businesses.