Stainless steel vs cast iron grates are pitted against one another, and has been the topic of much debate over the years. Higher end BBQ grills can ship with cast iron grates or stainless steel, but these are not the only options.
Truthfully, only the discerning BBQ enthusiasts care, nevertheless an important decision. But there is a difference, and the differences are always wrapped in compromise verses performance. Performance can possibly be seen as how well it cooks and produces nice grill markings.
I’ll use the word performance to also mean how long the grates will last and how easy are they to maintain. Like buying a car, there is a huge assortment of grates or “grills” do choose from, sometimes leaving the unknowing customer confused and frustrated. Maybe not frustrated, but really unsure of where to go as in many cases you can spend a lot of money on different types of grates.
Cheaper grills come with an assortment of thin poorly made flimsy looking cooking grates. These are usually some type of chrome plated steel grates. Higher quality BBQ’s have either steel or cast iron or offer both. To add to the fun, both cast iron and steel can be coated. Most commonly they are coated with a porcelain enamel.
Cast Iron Grill Grate Coatings
The BBQ and gas grill market place offers many variations of cast iron grates. Straight out of the box cast iron can be found on many BBQ and gas grill products. As I mentioned before, there are also coated iron variations. The most common iron grate coatings are porcelain coated iron grates, and enamel coated cast iron grates.
Each one tries to overcome the corrosive shortcomings found in pure cast iron. These coated iron grates don’t rust as much as pure cast iron grates. Also coating the iron grates eliminates the need to season the metal, and allows for more thorough cleaning. The coated iron grates no longer need to be oiled after use to prevent rusting. I should point out though that iron grates with a porcelain enamel coating are a bit more fragile than an uncoated iron grate.
Something as simple as dropping it on the patio stones could crack the enamel. The cracked enamel will eventually rust through. But if taken care of properly, these are easier to maintain and will last a long time. Pigments used in the manufacturing of the enamels, this can produce some pretty neat colors for you to choose from.
While enamel coated cast iron doesn’t have the seasoning and cleaning issues of bare cast iron, it can be much 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.
Closer Look at Iron and Its Alloys
Iron is a metallic element which is mined, and is typically referred to as iron ore. When smelted the iron is removed from the ore. After smelting, you get the basic raw material commonly referred to as pig iron. Pig iron is the raw material that cast iron is made of. Pig iron contains a lot of impurities as well as a lot of carbon. Cast iron is a pig iron with less carbon. The cast iron, being a ferrous alloy will be heated at a very high temperature, to its melting point.
The liquid iron is then poured into some type of mould to shape or "cast" the product. However if you work the iron prior to pouring it into a mould, you then have a "wrought iron". In simple terms, this is how iron is turned into its final product. To add to the confusion, steel is known as an alloy of iron. You can summarize the differences by saying that iron alloys with less than 2% carbon by weight, is known as steel. Any iron alloys with more than 2% carbon by weight, are knows as cast iron. The alloying process to make steel can vary greatly.
The addition of different elements can change the properties of the steel. Some benefits from the alloying process for steel is its increased resistance to rusting or corrosion. Also, for what its worth, steel is much better metal to weld with, from spot welding to MIG and TIG etc. So to summarize, alloys with higher carbon content are known as cast iron, lower carbon content, steel. Iron is less processed, steel is more processed than iron, stainless steel is again more processed than steel.
Cast iron can and will rust with improper care. As shown here, these are badly rusted and corroded cast iron grates. Would you want to grill a $10 porterhouse steak on these?
Cast Iron BBQ Grates Pros and Cons
Steel and Stainless Steel BBQ Grates
Plain old steel or blue steel as it is sometimes referred to is a hardy piece of metal. Blue steel will rust and corrode, but can take a pounding. It is rare to find basic steel grate on commodity BBQ’s and gas grills. You do find them when you are buying larger open pit type BBQ’s, where a large grate is needed to hold 20 chickens or 15 pork shoulders. This is rarely something you see next to the lawn chair. Commodity type gas grills, the Webers, Vermont Casting, Napoleon’s etc…
All these big players in the gas grill market offer stainless steel grates, in various sized and styles. Stainless steel will last a long time, and don’t need as much hand holding and cleaning compared to cast iron grates. After the first couple of cooks, the stainless grates will get dark and in some peoples eyes, "look like hell". We, its a gas grill? Not a surgical table. The darkening is normal and expected. Again by comparison, cast iron grates can and will rust and should to be oiled lightly.
Some grill manufacturers recommend leaving cooked food on the grates and once reheated the next time it is used, clean them off then. This isn’t needed on stainless. Blue steel and stainless steel won’t get as hot and won’t hold the heat as well as cast iron. Will it make nice grill marks on your meat? Yes it will. Will it be as nice as cast iron grates? With the right type of heat underneath, you can make really nice grill marks. High end grills will sell you stainless steel grates as an upgrade. These can be very nice grates, but come at a premium. Below are prawn being grilled on brand new stainless steel grates. Those are as big a grate as I ever care to use.
Stainless Steel BBQ Grates Pros and Cons
Thick Or Thin Grill Grates
The thickness of the grates is also the topic of much debate. Some of the big "BBQ thinkers" believe the thicker the grates, the less radiant heat is able to contact the meat on the grates. This is very true. The belief is the thick grates don’t cook the meat evenly. Through deductive reasoning, you can see that the BBQ pontiffs prefer narrow grates over wide ones. I tend to agree with this thinking. Sure thick grates look all sexy and fancy, but aren’t practical for an assortment of reasons.
The thicker they are, the heavier they are, and they also cost more money. Plus the newly gained knowledge that a thicker grate reduces your chance of an even cook. I don’t think a “thicker” metal grate has a significant impact on the evenness of the cooking process, but if you are after the perfect rib steak, the smaller metal grates will get you bigger smiles.