Are you thinking about grilling in a public park but the grill looks like the one in the picture above, all rusty? Or have you let your grill sit out in the elements for too long and now there are signs of rust on your grill grates?
If you’re wondering if it’s safe to grill on a rusty cast iron grill this article will not only give you the answer but also tell you tell you how to clean the grates and prevent this problem in the future.
So, Is It Safe?
Loose rust on a grill is not safe as it may stick to whatever you are cooking. Ingesting a little rust is probably not too harmful but over time it’s not something you want to put in your body regularly.
The Department of Physics for the University of Illinois says that rust is iron oxide which is benign (safe to consume) in very small quantities.
If the grill you are considering using has loose rust on it follow the tips in the next section to clean it before use.
If you’re in a bind and need a quick solution just put one or two pieces of aluminum foil down on the grill before placing your food on it. Crimping the ends of the foil around the bars of the grate will prevent it from moving or blowing away.
How to Clean a Rusted Cast Iron Grill
There are several ways to clean the rust and old food residue off of a cast iron grill grate. We’ll start with the quickest and easiest and work our way to the more complex but more thorough solutions.
Steel Wool / Aluminum Foil Ball / Wire Brush
These three options all work about the same. Balling up a piece of aluminum foil about one foot square and vigorously rubbing that along the grill grates should have the same effect as using a wire brush or steel wool.
The best way to clean a cast iron grill though is to use a moderately soft wire brush. Soft enough to not damage the cast iron, but strong enough to scrub away at the rust and grime.
One of the best wire brushes for this is listed on my Recommended Gear, under Best Grill Brush. You need a sturdy and many-layered brush like the one I recommend, so it will be safe to use on cast iron or ceramic grills.
This brush has 3 layers of wire, on the softer side, with a very sturdy handle that won’t bend when you use it. It’s also very easy to clean with a little soap and hot water, and will dry very quickly.
Full Strength Plain White Vinegar
Rub the rusty area with full strength plain white vinegar and let set for several minutes. Then rub the area with a wire brush or ball of aluminum foil and then rinse off with water. Vinegar is a weak acid and also good cleaner for grills as it is perfectly safe to consume if some is left on your grill while you are cooking.
Baking Soda Paste
Take half a cup of baking soda and add a little water. Continue to stir and add little amounts of water until you have a thick paste. Rub the paste on the grill and let sit for about one hour then scrub with a wire brush or aluminum foil ball. Rinse off when complete.
Kosher Salt Paste
If you find you need something a little stronger and more abrasive than the baking soda paste the next step up would be kosher salt made into a paste with water. Again, rub the paste onto the affected areas but this time you don’t need to let is set just scrub immediately with a wire brush or ball of aluminum foil. Rinse and repeat as needed.
How to Prevent a Cast Iron Grill from Rusting?
Knowing how to clean a cast iron grill is great but wouldn’t it be better to not let it rust in the first place? Here are some tips on keeping your grill in tip top shape.
Never Use Soap
There seems to be some varying opinion about using soap on a cast iron grill. It’s believed by some that the soap will ruin the seasoning on the grill by breaking down the oils. Others believe that the oils have been heated so many times that they are now polymerized oil that is safe to expose to soap. In my opinion it’s better to not use soap if you can clean the grill without it.
Never Soak Your Grill or Put It in the Dishwasher
Prolonged exposure to water will cause a grill to rust. Always dry your grill as soon as possible after cleaning it. Putting it in the dishwasher exposes it to water for a prolonged time but also to the soap in the washer.
Clean After Each Use
It’s tempting to close the lid of your grill and not think about it again till the next time you go out to cook. Proper cleaning of the grill will not only help prevent rust but also make your grill last longer. Cleaning will also cut down on the attractiveness of your grill to bugs and rodents.
Cleaning also helps the grill keep its seasoning and also helps the food to not stick.
How to Season a Cast Iron Grill
If you’ve scrubbed the rust off your grill grates you’ll want to season them to prevent future rust and food sticking.
- Make sure the grill is off and the grates are cold.
- Coat all the surfaces of the grates with a high heat cooking oil, such as peanut, corn or sesame.
- Wipe off any excess oil.
- Heat your grill with all burners on high for 18 minutes or until the oil starts smoking.
- Once the grill is cooled add a light coat of oil to the grates to prevent rusting.
Alternatives to Cast Iron Grills
If all this sounds like a lot of work you do have a few alternatives to cast iron.
Porcelain Coated Cast Iron
Cast Iron that is covered in porcelain is protected from rusting and does not need seasoning. It’s also easier to clean up. You have to be careful that you don’t chip the porcelain with metal grilling tools. Any chips will allow water to get into the cast iron and rust can occur.
Stainless steel grills are more resilient to the elements and don’t need seasoning. They don’t tend to get as hot as cast iron but they do keep their heat longer.