Seasoning Cast Iron With Chemistry

Back Story

Many people believe that camping is just a form of tolerating misery. Dr. Sheldon Cooper from the Big Bang Theory once said “if outside is so good, why has mankind spent thousands of years trying to perfect inside?”. I have been on many miserable, cold, wet camping trips. I sometimes do agree that you can be miserable when you camp. However, it is possible to make your campsite a comfortable and enjoyable home-away-from-home. One of these ways, is to bring a few things that will make your wilderness experience more enjoyable. Especially when car-camping, or canoe camping. The Dutch oven (a specific form of cast iron cook pot) is one of these tools. Although they are very heavy compared to stainless steel, they are incredible tools and help boost morale by providing some excellent meals in the back country. You do not have to clean or polish a Dutch Oven like you would Stainless Steel, as they are already blackened. Dutch Ovens also heat more evenly and provide a better cooking surface than other metals. Another added bonus is that trace elements of iron get into your food. Iron in your food helps build red blood cells. People who have iron deficiencies will often be advised to cook with iron cookware by their doctors. Once you have tried cooking in a dutch oven, you will not be interested in eating freeze dried foods, or military rations ever again when camping.

Buying Your Dutch Oven

There are various types of Dutch Ovens on the market. Look specifically for one designed for camping. This includes all metal construction, a flat top where you can put coals, and feet on the bottom which allow you put coals underneath the oven. You can buy Dutch Ovens brand new at army surplus stores, and camping supply stores. You may also find them used in antique stores and thrift stores. Just be sure you buy one with no plastic parts, as they will melt in the camp fire.

When you bring your Dutch Oven (or any cast iron cookware) home, be sure to run it under hot water and scrub it clean. It is a very common myth that you will damage your Dutch Oven if you scrub it with soap. Soap will not damage your cast iron Dutch Oven. However avoid soap if possible because soap can often leave a residue on the iron which will impede the fat polymerisation process.

Why “Season” your Dutch Oven?

This question is often asked by beginners but is easy to answer. The Dutch Oven is an ancient, and medieval method of preparing food. It is made with cast iron, which means the iron was made in a mould. The inside of these moulds are not smooth. There is no teflon coating, or non-stick coating whatsoever built into the pot.

Using an unseasoned pot will greatly increase risk of the pot cracking due to uneven temperatures and metal expansion.

If you use a non-seasoned pot you will end up with food that sticks and burns to the sides of the pot. It will create a huge mess and be almost impossible to clean – especially in the back country. Food will get stuck into the pores of the metal and you will not be able to get them out without damaging the Dutch Oven.

“Seasoning” your Dutch Oven, particularly with Flax Oil, will create a non-stick, glass-like surface on the pot which superior to any commercial non-stick coatings available on the market today.

Choosing Seasoning Oil

If you use your favourite search engine and type in “seasoning cast iron” you will notice there are literally dozens of different methods available to season your cast iron. The important thing to remember is that you are not simply baking oil onto the surface of the pot. The seasoning process described in this article is designed to cause a chemical reaction with the metal and create a process called “Fat Polymerisation”. This is a process in which we will use heat to cause a chemical change to the surface of the cooking pot.

Although many articles will state that any oil is useable to get a good high-gloss finish on your Dutch Oven. This is completely incorrect. There is only one drying oil which when dries, leaves a glossy, hard, glass-like finish.

As an outdoors person, think of what is used on traditional long bows, preserving outdoor furniture, and what artists use to mix with paint: Linseed Oil.

Linseed Oil is a drying oil which leaves a “varnish” on the surfaces of what it is painted on. This is why artists will often mix it with paint on canvas. Although Linseed Oil will give a great finish on your Dutch Oven, remember that as it is heated over time, the oil will leech into your food. It may not be a good idea to eat Linseed Oil.

The edible version of Linseed Oil is known as Flax Oil. You can often buy it in grocery stores, however if you visit a Health Food store, you may find a much better quality version of Flax Oil.  Health Food stores will carry Flax Oil with a whole list of credentials which are not only helpful in determining its quality, but are also good reason to increase the price. The Flax Oil used in this article was Gold Top Organics Flax Oil. It’s credentials were: Cold Pressed, Unrefined, Unfliltered, Organic, Trans-Fat Free.

Although Flax Oil is not the only way to season your Dutch Oven, you will find it the best oil to use. The reason for this is because Flax Oil is high in omega-3 fatty acids – specifically, alpha-linolenic acid (ALA). This oil, when heated releases free radicals which are what causes the polymerisation. Drying oils, which produce the hardest polymers, are characterized by high levels of polyunsaturated fatty acids, especially the omega-3 fatty acid ALA

Some people believe that free radicals cause harm to the body. However during the seasoning process, there is no food in the Dutch Oven. The seasoning process makes use of the free radicals, but they do not remain in the pot when the process is complete.

The Process

Seasoning a Dutch Oven is a relatively straightforward process. Begin by shaking your Flax Oil and pouring a small amount onto the Dutch oven. Rub it in and cover every square centimetre of the pot. Be sure to use your hands and get it into every nook and cranny of the pot. You don’t need much oil! Just enough to cover the entire surface of the Dutch oven.

Some people prefer to pre-heat the Dutch Oven to 93C (200F) in order to open the pores of the metal a little bit. This process facilitates the oil entering the cook pot the first time. This can make the pot difficult to handle, but it is a good process and will ensure the oils enter the metal and begin the process properly.

As you add the oil to your Dutch Oven, be sure that it coats it completely. Any areas which are missed can be re-covered later, as you will have to repeat this entire process at least 6 times before the Dutch Oven is ready for use.

Once the pot is coated with oil, the next step is to remove the oil. Use a clean, lint-free cloth and wipe down the pot. The concept is to ensure that the least amount of oil possible is on the pot as it is seasoned. Like dressing for winter, several thin layers are more effective than one big, heavy layer.

Do not be tempted to put a thick layer of Flax Oil on the pot. This will make a big mess. The oil will pool and fleck off through use and storage and cause an uneven cooking surface or worse, an area where food continually will stick to the pot.

It’s important to use the rag and get all of the oil you can off your Dutch Oven. This will ensure there are no pools of oil on the pot. Again, oil pools will not create a non-stick surface. The bubble will eventually transfer into your food and leave a non-treated spot inside the pot. This will make food stick to it until you season the pot again. It can also cause uneven heating of the metal, and make it crack. Patience is important with this process, there is no way to make it go faster, or cut corners.

Processing The Dutch Oven

When there is no dripping oil on the Dutch Oven, prepare your stove by pre-heating it to 260C (500F) or as close as your stove will go to 260C. Then, place your pot in the oven, and let it process for one hour. When the hour is up, do not open the stove! Let the stove cool naturally before pulling out your Dutch oven. This ensures the fat polymerisation process works properly. The reason we want the stove as hot as possible is because unrefined Flax Oil has one of the lowest smoke points of any oil at 107C (225F). The higher the temperature the more it will smoke, and that’s good for seasoning.

You can process more than one item in the stove at a time, including cast iron skillets, or whatever you need to. The more items you have in the stove, the better use of the resources (electric or gas) to power the stove.

During the processing of your Dutch Oven, be prepared for some smoke to fill your kitchen. This is a normal part of the process during the first couple of seasoning sessions. The more the Dutch Oven is seasoned, the less smoke you will have.

When this process is completed, and you remove your Dutch Oven the first time, it may look terrible. DO NOT BE ALARMED! If it looks uneven, splotchy, or that the process did not look perfect, that is okay. You will need to repeat this process six times to ensure the pot is ready for use. During that time, you will see the uneven areas of the pot disappear.

After the Dutch Oven has cooled, you can begin this process again. Coat the pot in oil, wipe it off, and leave it in the oven at 260C for an hour. Be sure to repeat this process a total of six times. Repetition will ensure that every part of the Dutch oven is coated, sealed, and treated for use.

Using The Seasoned Dutch Oven

After the seasoning of the Dutch oven is completed, it is ready for use. There are may websites dedicated to Dutch Oven Recipes, and it’s fun to experiment. My Siberian Husky loves it when I experiment with food, as she gets many meals which are unsuitable for human consumption.

The most important thing to remember about using your seasoned Dutch Oven is to keep a bottle of Flax Oil around. Make sure you keep it in your back country cooking kit, and put a  layer of it on the pot before you cook with it. Doing this allows you to maintain the finish on the pot, helps continue to build the non-stick surface stay slick, and ensures that there is no chance of various oils binding, mixing, or creating a mess inside your pot. Continuing to use Flax Oil will also keep your pot seasoned and remove the need for re-seasoning it in the near future.

To scrape your pot, you can use any spatula you wish. Just be sure it does not scratch the surface of the pot, or you will have to re-season it again. Metal spatulas such as stainless steel are perfectly acceptable to use in the pots, as long as they have round edges and you are gentle. Do not use abrasives such as steel wool on the pot, or it will scratch and damage your Flax Oil finish and you will need to re-season your pot again.

Homage to the Cast Iron Skillet

Do you have a black iron skillet? You are a southern mountain girl, I can’t imagine you would not. Put it on the kitchen table. Turn on the overhead lights.

Look into the skillet, Clarice. Lean over it and look down. If this were your mother’s skillet, and it well may be, it would hold among its molecules the vibrations of all the conversations ever held in its presence. All the exchanges, the petty irritations, the deadly revelations, the flat announcements of disaster, the grunts and poetry of love.

Sit down at the table, Clarice. Look into the skillet. If it is well cured, it’s a black pool, isn’t it? It’s like looking down a well. Your detailed reflection is not at the bottom, but you loom there, don’t you? The light behind you, there you are in a blackface, with a corona like your hair on fire.

We are elaborations of carbon, Clarice. You and the skillet and Daddy dead in the ground, cold as the skillet. It’s all still there. Listen.

— Hannibal Lector sends a letter to Clarice Starling in “Hannibal” by Thomas Harris

Works Cited

WHEATON, Paul (n.d.). How To: Cast Iron Skillet Non-Stick and Lasts a Lifetime. Retrieved 12 24, 2013, from Permaculture Articles by Paul Wheaton: http://www.richsoil.com/cast-iron.jsp

CANTER, Sheryl (2010, 01 28). Chemistry of Cast Iron Seasoning: A Science-Based How-To. Retrieved 12 24, 2013, from Sheryl’s Blog of ongoing explorations: http://sherylcanter.com/wordpress/2010/01/a-science-based-technique-for-seasoning-cast-iron/

CHU, Michael (2004, June 10). Smoke Points of Various Fats. Retrieved Dec 24, 2013, from Cooking For Engineers: http://www.cookingforengineers.com/article/50/Smoke-Points-of-Various-Fats

Tags: Cast Iron, Linseed Oil, Airforce, Army, Bear, Bear Grylls, Bruce Trail, bushcraft, camping, Canada, Canoe, Cast Iron, Cooking, David Arama, Falls, Feet, Ferro, fire, Grylls, Hiking, Hot Tent, Hot Tenting, Les Stroud, Mil-Spec, Military, National, Natural Plan Coop, Nature Connection, Nature Deficit Disorder, navy, Newspaper, Niagara, Niagara Falls, Online, Ontario, Outdoors, Outdoos, Packing, Park, Plus, product, Provincial, Provincial Park, Review, Rod, Starter, Stove, Surival, survivourman, survivorman, tent, BTC, survival, toes, Toronto, UK, Video, Wilderness, Wolfmaan, Radio, Terrestrial, Earth, Sol, Skyward, iTunes, Mac, Apple, Macbook, Vimeo, Military, Canadian Forces, Police, Podcast, Prepper