Researched and written by Divya Butani (The Veggie Wifey) & Meyer International (one of the largest manufacturers of cookware in the world)
If you’re serious about cooking, you will need all the right tools. As you probably already know, the quality of your food depends on the quality of your ingredients, but the least stressed part in any recipe, is the quality of your cookware. Cooking with the right kind of cookware is as important as buying the right, high-quality ingredients.
This article shares with you everything you need to know about the metals and coatings in cookware available today, and how to choose the right kind of cookware for you and your family.
Different Types Of Cookware
First, lets get the basics out of the way. There are only four main types of metal used in cookware: aluminum, steel, iron and copper. These metals are coated with several different types of materials which is why many people get confused when making the right purchase. There are also several variations and ‘marketing’ names used for the same kind of cookware.
Additional materials such as glass and clay/terra-cotta cookware are available too. These are mostly non-toxic (but as usual, it depends on the brand and how it is manufactured). Clay cookware is usually made using earth from non-industrialized non-farmed lands and glass is heated & blasted sand/stone. However, both require a lot of care while cooking and storing. Any quick/sudden change in temperature can cause the material to crack or worse, shatter.
Before we deep dive into the characteristics of each metal, I need to get some nerdy stats out of the way, just so you know how each metal works. This will make a lot of sense later.
The Thermal Performance
The thermal performance refers to the thermal conductivity and heat capacity of the metal. Thermal conductivity is the rate at which the heat passes through the metal and heat capacity is how much heat energy is absorbed. Heat capacity is sometimes referred as heat retention.
Thermal conductivity measured by watts per meter-kelvin (W/m.K) and heat capacity is measured by joule per gram per degree Celsius (J/g·°C). The higher the number for thermal conductivity means the faster the transfer of heat. The lower the number for heat capacity means the less energy needed to retain that temperature.
Here is a table to show you the different thermal conductivities and heat retentions of each metal.
|Metal||Thermal Conductivity (W/m.K)||Heat Retention (J/g·°C)|
2. https://material-properties.org 3. https://www.engineersedge.com/materials/specific_heat_capacity_of_metals_13259.htm
Interpreting This Data
- Copper is the best metal to transfer heat, making it distribute heat evenly, and it is also the best metal to absorb heat. This metal can also cool down fairly quickly.
- Aluminum can transfer heat fairly quickly, but it is a poor metal for absorbing heat
- Iron takes longer to transfer heat, distributing heat unevenly, but is the second best at absorbing the heat, and retaining heat.
- Cast iron and carbon steel are both similar in terms of heat transfer as both take longer to heat up, but cast iron can absorb heat better than carbon steel. Iron and cast iron are the second best metals (after copper) to absorb and retain heat.
- Stainless steel is the ‘slowest’ metal for heat transfer, making the distribution of heat very uneven, but it is a great absorber of heat.
What Is Each Metal Best Used For?
- Copper cookware is used by candy makers, chocolatiers, and when cooking sauces because its a metal where you can control the temperature accurately.
- Aluminum is a very common metal in everyday cookware. Its ability to transfer heat quickly and its light weight makes it ideal for everyday cooking and baking. It has several coating variations in the market, which makes choosing the right kind of aluminum confusing. I will explain more about the coatings below.
- Iron (pure iron/wrought iron cookware) is mostly used for woks and kadais, for more traditional forms of cooking. It’s malleable and expands when heated, therefore it can change shape over time. It is durable, but not necessarily nonstick.
- Cast iron has recently become a common form of iron cookware. It is best used for high-temperature cooking such as frying, deep-frying and slow-cooking. It is not malleable, it is hard and very strong. It is nonstick and can become increasingly nonstick over time due to its seasoning (if seasoned correctly).
- Stainless steel is great for searing, roasting and boiling as the heat retention is quite high. It is perfect for creating that beautiful golden sheen on your food.
Here is an A-Z, comprehensible, easy to digest, breakdown of everything you need to know about these metals, the differences between each one and how each metal affects your cooking:
Metal Type: Aluminum
Alternate Names: Non-Stick/Hard-Anodized/Standard Anodized
What you need to know:
Aluminum is by far the most common metal used in cookware. It a great conductor of heat, and cools down very quickly as it is not a good absorber of heat, which is why so many cookware brands use this metal for their cookware.
However, there are several things you need to know about this metal in your cookware.
- Uncoated aluminum is not safe because it is highly reactive to acidic foods. This means, when anything like tomatoes are cooked in it, the metal can leach into your food, making it toxic. This is why aluminum cookware should always be coated with a non-stick layer, or ‘anodized’ (an electrolytic process to coat the aluminum with a layer to protect the metal from leaching into food)
- Coated aluminum means that the aluminum is coated with a special material to make it non-stick. There are several non-stick coatings available in the market today. Some are toxic, some are not. The coatings available in the market range from Polytetrafluoroethylene (PTFE) or its common brand name ‘TEFLON’ (a brand of PTFE owned by DuPont), Perfluorooctanoic Acid (PFOA), ceramic coating, marble coating, enamel coating and many more.
The PTFE/TEFLON and PFOA Debate:
PTFE and PFOA are not the same. In a nutshell, PFOA is toxic, which is why so many brands label their cookware as PFOA-free. It is toxic because the IARC (International Agency for the Research on Cancer) found some evidence that showed PFOA can cause cancer, specifically kidney and testicular cancer. However, PTFE is deemed safe to use UNLESS when heated over 260 degrees Celsius (but no one should be cooking over this temperature anyway).
There is still a lot of back and fourth about this between the experts and lots of contradictory information on the internet about this. If you do a quick search, you will see several articles claiming PTFE/TEFLON is toxic.
My take: most non-stick pans are coated with PTFE because thats exactly what makes it non-stick, BUT if you use a very high-quality nonstick pan, that is hard anodized and coated with ceramic or marble, you’re better off (more about hard anodization below). It also comes down to how you use your non-stick. Do not heat your non-stick to a very high temperature, it should only be used for low temperature cooking, that is also quick.
- Hard anodization is a process that makes the aluminum metal thicker, have a higher abrasion resistance, and has a more uniform surface compared to the standard process of anodization. This is special surface treatment for aluminum that has recently made its entry into the market. It involves oxidizing the metal to plug and seal the porous layers of the metal, creating a smoother, stronger finish that can also enhance its resistance and durability.
This process makes a super hard material that is 8 times harder than regular aluminum and twice as hard as stainless steel. Normally, this type of processed aluminum is coated with a beautiful finish, but what makes this type of cookware different from the others is the ability to hold on to the nonstick coating a lot stronger than standard anodization.
Just to be clear, all hard-anodized cookware is also considered non-stick because it has been coated with PTFE BUT not all non-stick cookware is hard-anodized, because anodization is a process for the base material: aluminum. When shopping for your cookware, make sure it says ‘hard anodized’ or ‘black alumite‘. Black alumite is the same as hard anodization.
Metal Type: Stainless Steel
Alternate Names: 3-ply/5-ply/7-ply/Cladded
What you need to know:
Stainless steel cookware is made up of mixed metals that include chromium and aluminum. This type of metal heats slowly, transferring heat unevenly. It is ideal for roasting and searing, and has long handles to keep your hands cool while cooking.
This type of cookware is ‘cladded’, which means the inner core (base metal) is a copper or aluminum metal, surrounded by layers of stainless steel.
This is why you have measurements of 3-ply, 5-ply or even 7-ply when it comes to stainless steel. The ply-refers to the number of layers in-between the core metal (aluminum or copper) and the exterior.
The more ply does not necessarily mean higher quality cookware, it simply translates to a more even heat distribution. For example, 3-ply will have fewer layers to transfer heat, therefore, your food may sear differently than a 7-ply pan, as a 7-ply pan has more layers for the heat to transfer.
Regarding upkeep, stainless steel does last very long and is very durable. It also does not have any nonstick coatings. However, is prone to grease and food stains, making it difficult to clean at times. It also can be quite expensive.
Metal Type: Iron
Alternate Names: Cast Iron/Enameled Cast Iron/Porcelain Cast Iron/Uncoated Cast Iron/Uncoated Pre-Seasoned Cast Iron
What you need to know:
Iron or wrought iron cookware is pure iron that has been heated up and shaped into different pots and pans. Wrought iron is extremely malleable and expands when heated. This is how it gets stronger and stronger over time when used often, but it does change shape.
Cast iron is made of iron and other metal scraps, smelted and poured into moulds. This makes it non-malleable and extremely strong.
Iron rusts when moisture is left on the surface. Some cast irons are coated through seasoning (oil being infused into the pores of the metal through heat making it nonstick) or with enamel or porcelain to protect it from rusting. This type of coating leaves a very smooth finish and makes it durable in terms of washing, and cleaning up.
Coated cast iron: enamel and porcelain are two different coating materials. Enamel is a glassy coating baked onto metal, while porcelain is hard, white and translucent coating that is made from firing up a material called kaolin (a type of clay). Porcelain enamel is a hybrid of this. It is essentially made from glass and is non-toxic.
You don’t see the rust on the coated cast iron, but, it can stain easily. Cooking with sticky, acidic foods can leave a tough stain on this type of cookware so maintaining this does take effort. Additionally, I have noticed a difference in cooking time from using a coated cast iron, and uncoated cast iron. I personally noticed it took longer to cook in the coated cast iron cookware, than it does with an uncoated cast iron cookware.
Utensils like silicone or wood are best to use on any cast iron cookware, as the utensils should glide against it rather than scratch the surface.
Uncoated pre-seasoned cast iron is extremely durable, and naturally non-stick, and chemical-free. It has a very high heat retention, making it perfect for sautéing or roasting/deep-frying. It also is very affordable and long-lasting.
Uncoated cast iron cookware does require good upkeep as it needs oiling after every wash to prevent it from rusting. However, before you use this, you need to season it yourself.
Metal Type: Copper
What you need to know:
Best distributor of heat, but very difficult to maintain as it can form the green film over the edges called patina. Additionally, copper cookware is extremely expensive.
Heating copper can leach into your food causing copper poisoning, so copper cookware is not necessarily safer.
However, copper metal lined with another metal like stainless steel is widely used in restaurants around the world. Lining the copper protects food from interacting with the metal, avoiding metal poisoning and the sort.
Other Metals and Coatings
Carbon steel is made up of both carbon and iron, which are both safe for cooking, its much lighter than cast iron, and unlike uncoated cast iron pans, it can be used for cooking eggs, and crepes because of the even, smoother surface. It is also great for sautéing.
Caring for your carbon steel pan is the same as your cast iron, it is prone to rusting, so coating it in a high smoke point oil after gently washing it with light soap and water can prevent it from rusting.
Carbon steel pans heat up much quicker than cast iron pans, and due to its conductivity, it heats up more evenly.
Alternate Names: Granite/Marble/Mineral/Ceramic ‘COATING’
Deemed as the safest coating on aluminum cookware, this ‘stone’ coating cookware contains either carbon steel, aluminum or stainless steel as a base metal, but it is finished with extremely durable, high-end non-stick coatings like granite, marble, and other stones.
It heats up evenly, and keeps food warm for longer. These coatings are quite new to the cookware manufacturing scene, and said to be much safer than other PTFE non-stick coatings.
Marble coating is a highly sophisticated manufacturing process where very tiny particles of marble is made into nano-marble non-stick coating. When applied to the base metal, it creates highly durable non-stick, scratch resistant marble-like frying pan. Sometimes it is also sprayed on and an external layer to amplify the heat resistance and durability.
Ceramic coating is another type of new age coating which is a mixture of clay, and other man-made materials in order to give the appearance of marble. It is as sophisticated and durable, as well as non-toxic. When you see ‘ceramic marble’ coating on the packaging of this type of cookware, it simply means it looks like marble, but its ceramic.
So…What Is Toxic Cookware?
Essentially, cheap cookware that smells funny when heated, any coating that you notice scraping off the pan, PFOA coating and uncoated aluminum are all toxic and poisonous. If you have no idea if your pots or pans have any of the chemicals above, I would highly suggest you research them extensively before continued use or purchase.
Going for PFOA-free and where possible, PTFE-free/TEFLON-free high-quality marble or ceramic coated hard anodized aluminum, pre-seasoned or not pre-seasoned cast iron, which is chemical-free if uncoated, 5-7ply stainless steel, carbon steel are all great options.
Maintaining your cookware is also so important. You can have the most expensive cookware but if you don’t maintain it correctly, it can possibly do more harm than good. Finally, knowing how to use your cookware is key.
Each metal has its advantages and disadvantages as you have read above. Heating nonstick extremely high, or using that for deep frying is not beneficial. Understanding these aspects of your cookware can help you make better judgements about what is safe and what is not safe to use for you and your family.
My itch to write this article came about after I noticed the surface of my nonstick pot coating sprinkled all over my rice. I started to worry about how much of this I ate already and if it would have any adverse effects on my health, but more importantly, my kids health. My Google research was endless. This is why I came to my IG fam on 4th January 2022 and asked what cookware they believe and trust, several months ago.
I started researching all sorts of cookware, and this is how much research I have done. The number of cookware options are endless, so I hope this article has been helpful for you to understand it better.
Before I forget, the handles are also a very important topic when discussing the right cookware for you. If your cookware uses handles that are cushioned with low-quality rubber, it is most likely the heat will melt it off, releasing carbon monoxide and cyanide. The fumes can certainly harm your health. It may even melt onto your food and you may end up eating it. No rubber handles are good for you.
Silicone handles can withstand high temperatures (up to 230 degrees Celsius) so using silicone handles are a much better option than rubber.
You should never put any material other than metal in your oven, even if the label says oven safe.
Finally, What Do You Really Need In Your Home Kitchen?
You certainly need a mixture of metals and coatings if you’re going to invest in making good food. There is yet to be a cookware range that includes the essentials of nonstick, stainless steel, cast iron and carbon steel. Imagine having on set that includes all of this! There is nothing like this in the market.
It is vital to have a range of cookware ONLY because you use different pots and pans for different cooking methods. Deep-frying needs a durable, high-temperature absorbing metal. Eggs and crepes need a good nonstick coating that is non-toxic. Stainless steel with a good 3ply is best for boiling and roasting.
I would certainly recommend having a look at what food you cook on the regular and deduct what pots and pans you need from there.
- If you cook lots of liquid foods that solidify through cooking, you definitely need a high quality non-stick pots & pan, either in the 20cm and 26-29cm range. I would recommend this non-stick chef’s pan or this frypan. I recently used this nonstick wok, and found it so easy to cook fried rice in. Having a large wok + lid set in the house is amazing for stir-fry anything.
- If you make a lot of food that needs long, slow or high temperature cooking, cast iron is the best. I would highly recommend this range of uncoated, pre-seasoned cast iron because it is chemical-free and durable. I use the 24cm sauteuse a lot, it is multi-purpose. I also really like that the lid that comes with each product can be used for any of the pots and pans in the same size. The tava is also a great addition to your cast iron collection if you cook rotis, chilla and naan often. 26cm is a good size, 28cm would be a little too big for storage.
The beauty about cast irons is that it gets more non-stick after every use (if used correctly). It takes a lot of effort to maintain it well, but a good cast iron collection can truly last a lifetime or even generations. It is strong, sturdy, and can withstand extremely high heat without affecting your health. I have used this collection for over 2 months now, and compared to my coated cast iron pans, this heats up better, cooks faster and is high-quality, making it outstanding value for money.
- If you cook a lot of sauces, need to sear, roast, or boil a lot of food, I would recommend this range of stainless steel. A good stainless steel pan gives your meal a beautiful golden brown shade that no other pan can give, and it absolutely perfect for cooking your pasta sauces. Something in between a 26-29cm range would be ideal for a family of 4. The shine that bounces off stainless steel not only makes cooking attractive, but it also makes it easier to understand the food you’re cooking. It’s clearer to see your ingredients, allowing you to cook to perfection. Every household should have one stainless steel stock-pot in their kitchen, between 7-10L. It’s amazing for boiling anything.
Other cookware like carbon steel and copper are non-essential. However, carbon steel may be a great alternative to a very heavy cast iron.
If you have any questions regarding any of the information above, don’t hesitate to get in touch with me via the contact form on the website.
Don’t forget, use MEYERxTVW for a 10% discount on your nonstick and cast iron purchases made through the MEYER website. This is a global discount and can be used no matter where you are located in this beautiful world.
I hope you found this information useful. Happy cooking!