Cast iron cookware are valued for their heat retention properties, and can be produced and formed with a relatively low level of technology. Seasoning is used to protect bare cast iron from rust and to create a non-stick surface. Types of bare cast iron cookware include panini presses, waffle irons, crepe makers, dutch ovens, frying pans, deep fryers, tetsubin, woks, potjies, karahi, flattop grills and griddles.
Bare cast iron vessels have been used for cooking for over two thousand years. Cast iron cauldrons and cooking pots were valued as kitchen items for their durability and their ability to retain heat, thus improving the quality of cooking meals. In Europe, before the introduction of the kitchen stove in the middle of the 19th century, meals were cooked in the hearth or fireplace, and cooking pots and pans were designed for use in the hearth. This meant that all cooking vessels had to be designed to be suspended on, or in, a fireplace. Cast iron pots were made with handles to allow them to be hung over a fire, or with legs so that they could stand up in the fireplace. In addition to Dutch ovens, which were developed with the onset of the Industrial Revolution, a commonly used cast iron cooking pan called a spider had a handle and three legs used to stand up in the coals and ashes of the fire. Cooking pots and pans with legless, flat bottoms were designed when cooking stoves became popular; this period of the late 19th century saw the introduction of the flat cast iron skillet.
Cast iron cookware was especially popular among homemakers and housekeepers during the first half of the 20th century. Most American households had at least one cast iron cooking pan, and brands such as Griswold and Wagner Ware were especially popular. Although those companies folded in the late 1950s and the brands are now owned by the American Culinary Corporation, Wagner and Griswold cast iron pots and pans from this era continue to see daily use in the present day; they are also highly sought after by antique collectors and dealers. The Lodge Manufacturing company is currently the only major manufacturer of cast iron cookware in the United States, as most other cookware suppliers use pots and pans made in Asia or Europe.
The 20th century also saw the introduction and popularization of enamel-coated cast iron cookware.
Cast iron fell out of favor in the 1960s and 1970s, as teflon-coated aluminum non-stick cookware was introduced and quickly became the item of choice in many kitchens. Today, a large selection of cookware can be purchased from kitchen suppliers, of which cast iron comprises only a small fraction. However, the durability and reliability of cast iron as a cooking tool has ensured its survival, and cast iron cookware is still recommended by most cooks and chefs as an essential part of any kitchen.
Bare cast iron
Cast iron's ability to withstand and maintain very high cooking temperatures makes it a common choice for searing or frying, and its excellent heat retention makes it a good option for long-cooking stews or braised dishes. Because cast iron skillets can develop a "non-stick" surface, they are also a good choice for egg dishes. Other uses of cast iron pans include baking, for instance for making cornbread, cobblers and cakes.
Most bare cast iron pots and pans are cast as a single piece of metal, including the handle. This allows them to be used on both the stovetop and in the oven. Many recipes call for the use of a cast iron skillet or pot, especially so that the dish can be initially seared or fried on the stovetop then transferred into the oven, pan and all, to finish baking. Likewise, cast iron skillets can double as baking dishes. Cornbread in particular is seen as a food item that is best prepared in a cast iron skillet: the iron pan is heated beforehand in the oven, the ingredients are first combined and mixed in a mixing bowl, then added to the heated pan, and the dish is then placed directly into the oven for fast baking. This differs from many other cooking pots, which have varying components that may be damaged by the excessive temperatures of 400 °F (204 °C) or more.
Cast iron is a very slow conductor of heat and forms hot spots if heated too quickly, or on an undersized burner; however, it has excellent heat retention properties, and the entire pan will eventually become extremely hot, including the iron handle or handles.
An American Dietetic Association study found that cast iron cookware can leach significant amounts of dietary iron into food. The amounts of iron absorbed varied greatly depending on the food, its acidity, its water content, how long it was cooked, and how old the cookware is. The iron in spaghetti sauce increased 2,109 percent (from 0.35 mg/100g to 7.38 mg/100g), while other foods increased less dramatically; for example, the iron in cornbread increased 28 percent, from 0.67 to 0.86 mg/100g. Anemics, and those with iron deficiencies, may benefit from this effect, which was the basis for the development of the lucky iron fish, an iron ingot used during cooking to provide dietary iron to those with iron deficiency. People with hemochromatosis (iron overload, bronze disease) should avoid using cast iron cookware because of the iron leaching effect into the food.
A seasoned pan has a stick-resistant coating created by polymerized oils and fats. Seasoning is a process by which a layer of animal fat or vegetable oil is applied and cooked onto cast iron or carbon steel cookware. New cookware should be vigorously washed in hot water with a strong detergent to remove any casting oils from the cookware's surface. A light coat of oil is applied and the cookware is placed upside down in an oven above a large pan (to drain for an hour), the pan can now be removed, then the oven set to 350 degrees Fahrenheit (180 degrees Celsius) and baked for 30 minutes. Some cookware comes pre-seasoned from the factory. A proper cast iron seasoning protects the cookware from rusting, provides a non-stick surface for cooking, and prevents food from interacting with the iron of the pan. However, frequent use of acidic foods such as tomato sauce can remove the seasoning faster and the cookware will need to be re-seasoned frequently. This can be lessened if initial season is better at polymerizing than standard fats/oils. Enamel-coated cast iron pans do not need seasoning, as the enamel coating prevents rust in most instances. It is recommended to maintain the seasoning frequently to keep the food from sticking to the iron.
Because other cookware cleaning techniques like scouring or washing in a dishwasher can remove or damage the seasoning on a bare cast iron pan, these pans should not be cleaned like most other cookware. Some chefs advocate never cleaning cast iron pans at all; simply wiping them out after use, or washing them with hot water and a stiff brush. Others advocate washing with mild soap and water, and then re-applying a thin layer of fat or oil. A third approach is to scrub with coarse salt and a paper towel or clean rag.
There are many producers of traditional cast iron in France, Italy, Denmark, Sweden and the UK, manufacturing enameled and enameled cookware. In Asia, particularly China, India, Korea and Japan, there is a long history of cooking with cast iron. Well-established brands in the United States include Griswold and Wagner (both brand names owned by the American Culinary Corporation), Camp Chef, Lodge, Bayou Classic, and John Wright.
The decline in daily use of cast iron cookware contributed to the closure of nearly all iron cookware manufacturers in the United States. By the beginning of the 21st century, Lodge Manufacturing was the only remaining manufacturer of cast iron cookware in the United States; all other makers had closed. However, cast iron saw a resurgence of its popularity in specialty markets, as cooking shows and celebrity chefs brought renewed attention to traditional cooking methods, especially cast iron. In the 2010s, small startup companies such as FINEX, Element Cookware and Borough Furnace were founded, especially to produce new cast iron cookware for specialty cooking markets; typically, these pans were high-priced and not meant for everyday purchases, in the manner of "luxury" cookware such as Le Creuset and Staub.
Enameled cast iron
Enameled cast iron is cast iron that has a vitreous enamel glaze. The enamel coating over the cast iron prevents rusting, eliminates the need to season the metal, and allows more thorough cleaning. Furthermore, pigments used in the enameling process can produce vibrant colors. While enamel coated cast iron doesn't have the seasoning and cleaning issues of bare cast iron, it can be several times more costly, and does not have some of the benefits of bare cast iron, such as the ability to withstand searing heat and resist sticking. It limits the leaching of dietary iron, and chipping of the enamel coating can be a concern.
Well-known manufacturers of enameled cast iron cookware are Cousances, Le Creuset, Tramontina, Le Chasseur, Lodge, Staub, Descoware, and John Wright. Several newer brands are associated with well-known celebrities and chefs, including Daniel Boulud Kitchen, Martha Stewart, Rachael Ray Cookware (made by Anolon), and Mario Batali (made by Copco).