Cast iron cookware has been a cooking vessel for over two thousand years. However, they are not so popular in modern life until cooking healthy concern becomes the focus in our daily life recently.
According to the definition of WIKIPEDIA, cast iron cookware is heavy-duty cookware made of cast iron that is valued for its heat retention and durability. The article will tell you almost everything that you need to know about iron cookware material, its manufacturing workmanship, and cooking features. Also, we will go over some tips on how to make seasoning to prevent it from rusting and keep it in good condition. Besides, a general classification will be introduced too so that you may have a clear picture of selection for your custom need.
History of Cast Iron Cookware
As well known, cast iron was developed during the 5th century B.C. in China due to metallurgy technology breaking through on melting furnace. It was originally used to make plowshares, pots, and pagoda parts. Then later, iron cookware and metallurgy technology spread into Europe through silk rod around the A.D 12th century and got rapid development in A.D 18th century. Also, the stove got popular in-house cooking at that time, so it is possible to make iron cookware much thinner and lighter in a mass-production way. As a result, cast iron cookware got popular gradually.
Cast iron cookware even became a sign of wealth. The famous economist Adam Smith has ever mentioned that in his famous book <<The Wealth of Nations>>. The nation’s fortune comes not from how much gold they have, but from the cast iron cookware that they can produce.
Later in the 19th century, the emerging stainless steel and Teflon coated aluminum cookware has the competitive advantage of lightweight and fast heat conductivity. Because of that, the iron cookware market share got downward and out of people reach gradually.
Material Metallurgy Structure
Iron cookware material is made from pig iron that is refined from iron ore. Pig iron is an alloy of iron and carbon chemical elements and includes other minor alloying chemical elements, such as silicon, manganese, phosphate, and sulfur.
The percentage of carbon in iron casting is normally between 2.11%~4.3%. The most of carbon element exists as graphite condition, and a small percentage exist in metallurgy matrix with iron element after iron water solidified in a sand mold. According to the type of metallurgy matrix and graphite shape, iron casting material may be classified into four catalogs. The major catalog, accounting for 80% of iron casting, is the Grey iron casting.
The graphite that exists in grey iron casting is mainly flaked shape. Because the color of casting fracture is grey, so it is called grey iron casting. In addition, the metallurgy matrix of grey iron casting has three basic types: ferrite, ferrite+ pearlite, and pearlite. Which type of matrix exists is depending on how many percent carbons are dissolved in the metallurgy matrix, and this is achieved through controlling the cooling rate of casting after iron water poured into the sand mold.
Cast iron cookware is normally made through the sand casting process. Firstly, pig iron, recycled steel scrap, and riser melt in foundry furnace, then slag remover and carburant is added to remove impurity and increase carbon ratio.
Once the iron water temperature reaches the pouring point, the worker will pour iron water into the sand mold along with the nucleating agent. After casting cools down, sand mold will break away to release cookware casting out. Consequently, sandblasting or shot peening process will remove surface oxidation or adhesive sand to get the desired surface finish. Finally, the finished casting is cleaned, dipped in a food-grade wax, or water-based rust inhibitor to prevent it from rust in storage or shipping.
Furthermore, iron casting may be pre-seasoned or enameled in foundry factories so that they are ready to be used once delivered to user's hands.
The Nature of Cast Iron Cookware
From the imagination of most people, cast iron is an old-fashioned, heavy, poor heat conductor, and hard to take care of. Further, they are easy to get rusted and fragile. However, iron cookware has much inherent advantage suitable for cooking, they are easy to use and care for actually. Most importantly they are economical, versatile, and durable.
The thick-walled and heavy iron cookware is capable to retain heat for a long time. Thus, they can continue cooking after the heat source being turned off! As such, it has a nostalgic appeal that other cookware doesn’t have. Moreover, the most important is that it has no non-stick chemical plastic film!
Nevertheless, cast-iron cooking has been popular around for hundreds of years, and still has a place in today’s kitchen, especially when the non-stick Teflon coating has been a rise in health concern.
Enameled Cast Iron
Enameled cast iron is iron cookware that has a vitreous enamel glaze applied to the surface. Therefore, it may achieve variable colors with food-grade pigment added in the glaze. As a result, the enamel prevents it from rusting, eliminates the seasoning requirements, and allows thorough cleaning.
However, it also lost the non-sticking characteristic of bare cast iron and the ability to withstand searing heat. In addition, enamel coating will get crack or chipped if the pan gets drop impact, overheating, or hot pot quenching with cold water. Nevertheless, it is excellent for slow simmering!
Cast iron cookware is in a variety of shapes and sizes. Hence, we can find all sorts of pans and pots, as well as specialty items.
Cast iron skillet (show in the right picture) comes in a variety of sizes, from very small 6 inches in diameter to size over 15 inches in diameter. The average depth of these skillets is between 1-1/4 inch and 2-1/2 inches, depending on the size of the pan. In addition to standard, square skillets are also available. These skillets are great for a number of cooking tasks, on the stove or in the stove, such as baking, pan-frying, roasting, and simmering.
Cast iron fry pan is similar to skillet except that the sides of fry pan are deeper (usually 3 inches or deeper) so that the grease does not splatter as much when frying (see right picture)
Frypans can perform many of the same cooking tasks that skillet can do. Because of the depth of the pan, fry pans can do extra tasks as below:
- Deep frying: food may be submerged in hot oil instead of cooking it one side at a time as doing in a skillet
- Simmering stews and soup
- Slow cooking foods on the stovetop
Griddles and grill pans
Cast iron griddle can be round, square, or rectangular, and may be in various sizes (see the right picture). The smooth surface and shallow sides are perfect for making pancakes, hot sandwiches, frying egg, bacon, roasting vegetables, and pizza
Cast iron grill pan, shown in the right picture, are exactly what they sound like: pans that can grill food (vegetables, seafood, meat, and so on), either on a stovetop or over a campfire. Besides, the ribbed bottom keeps food out of dripping and leaves nice sear marks, much like that from cooking on an outdoor grill.
A dutch oven is deep-sided pots with lids that you can use on the stovetop or inside the oven. They are the original slow cookers (see the right picture). But people may use a versatile Dutch oven for more than slow cooking, such as baking, deep-frying, pan-frying, and simmering.
The dutch oven has two catalogs: indoor and outdoor. The differences between them are as following:
The lid. The indoor oven has a domed lid, and the lid of the outdoor oven is generally flattered and is flanged (has a lip around the rim) so that coals can be put on the top of the lid.
The bottom. Indoor ovens have flat bottoms, outdoor ovens have three short legs to keep the oven above the fireplace.
The skillet, pots, and griddles comprise the basic collection of cast iron cookware. However, special pans, bakeware, and serving ware are available, such as corn-stick pan, cake pans, serving platters, fish pans, and so on.
Cast Iron Cookware Seasoning
Because of the rough and porous surface, people have to season new iron cookware before use, and re-season old cast iron periodically.
Seasoning, also curing, is the process of filling cast iron pores or void and smoothing rough texture with oil, thus creating a smooth and non-stick surface. Basically seasoning process is to cook oil into the pan, and also serve a purpose to protect the iron pan from rusting.
The seasoning steps are as follows:
The new cast iron from the factory, if not preseasoned, is covered with a food-grade wax or water-soluble rust inhibitor. So the first step is to scrub the pan by using the hottest water that you can stand, mild dish detergent or soap, and a scouring pad (not steel wool). Be sure to scrub all surfaces of the pan: the bottom, the handle, inside and outside.
Dry cookware thoroughly
Clean excessive water using a paper or dish towel, or put the pan on a burner and let it warm up evaporate all moisture left.
Preheat baking oven
Prepare an aluminum foil on the bottom rack of the oven, the foil will catch excessive oil dripping off from the pan. Make sure the foil covers the area underneath the cast iron pan. If you prefer, a baking sheet may be an alternative replacement of aluminum foil put directly under the cast iron. Turn on the oven switch, and set the temperature to 350 degrees Fahrenheit (180 degrees Celsius).
Applying shortening or vegetable oil
Put the cast iron pan on a stovetop burner and melt about a tablespoon of shortening or vegetable oil in it. Using a paper towel or sponge, wipe the entire surface of the pan, including tops, bottoms, handles, and legs. Only applying a thinner layer of oil, wipe excessive away if the oil is pooling or dripping.
Put the oiled pan upside down in the oven so that any excessive shortening or oil drips off on aluminum foil underneath the bottom rack of the oven. Keep the pan inside of the oven, and set baking time 1 hour. When the time is up, turn off the oven, and leave cookware in the oven until the oven cools down. The pan is still baking and achieve a deeper cure while the oven cools.
The properly seasoned cookware has a light layer of shortening or polymerized oil. Hence, the surface is rust-resistant and non-stick for cooking and reduces food interaction with the iron of the pan. However, iron cookware must be re-seasoned again if exposed to acidic foods, such as tomatoes.
Cast iron can be great cookware. It’s tough enough to withstand plenty of rough treatment, and people don’t have to worry about scratching it. But it does require special care to keep cast iron in cooking health.
- Don’t use soap or cleaning detergent. The soap effectively cuts through oil and grease that is what the seasoning is. However, if a dish soap is positively needed, it is necessary to re-season the pan after each cleaning.
- Don’t use a wire brush or steel wool scouring pad. Using hot water and a scrub brush, scrub the cooking surface with a natural-bristled or stiff plastic brush. In case of any stuck-on bit of food, it usually requires to scrap the side and bottom with a spoon as an assistant cleaning method.
- Don’t soak cast iron, and let it dry in the air. Once cleaned up, never let cast iron drip dry, or let it sit on top of anything, or touch anything that has moisture. Immediately and thoroughly dry the cast iron with a towel, and put the pan on a burner or oven for a few minutes to bake moisture out. Coat the cast iron with a thin layer of vegetable oil while it is still warm and wipe it dry with a paper towel.
- Never wash cast iron in the dishwasher, detergent will scribe away the seasoning.
- Don’t pour cold water into hot cast iron, it may cause cookware crack or break
So there have many using warnings, and it makes you feel that cast iron cookware isn’t worth the effort to keep. However, these care instructions aren’t different from the instructions that come with much expensive cookware. For cast iron, if we don’t follow the care and cleaning instructions, the problem we face is the risk of ruining the seasoning surface, but we can fix it. Considering the advantage of cast iron cookware, the warning issue in the application doesn’t matter really, and it is worth it for us to possess it.
In conclusion, although iron cookware lost its dominant power in the cookware market, however, it still has its value. In recent years, people have much concerned about cooking health, especially about the cancer cause by Teflon-coated cookware. As such, cast iron cookware is enjoying a resurgence of popularity in the 21th century because of its natural, healthy, and nostalgic characteristics.
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