HOME > Chowhound > Home Cooking >


Is rock salt edible?

  • m


I have a salt mill that is like a pepper mill, except it is obviously filled with salt, a very coarse grade, and then you grind it onto your food. The time has come to re-fill it, and I don't know what type of salt to use. I have a box of rock salt and was considering that, but then it occurred to me that I don't know if rock salt is edible! I mean, it's used to freeze ice cream (ice/salt mixture) but that's the only use I've ever heard of for rock salt. Anyway, does anyone know? Or, what type of salt should I re-fill my salt grinder with and where can I get it? Thanks!

  1. Click to Upload a photo (10 MB limit)
  1. Look on the ingredients list. If it just says sodium chloride you should be fine. That is chemist-speak for table salt.

    Usually it is used as a bed for baking oysters, for melting snow, etc, as you mentioned.

    1. I'm sure it's edible. The problem is it's so coarse. You could probably use it in your grinder and be fine. Still, salt is cheap. I'd go buy a box of kosher salt and be done with it. Save the rock salt for your ice cream maker.

      1. You should be able to buy coarse Sea salt in a round tin at the grocery store that will work in your salt grinder. Don't know about rock salt.

        1. Rock salt is full of impurities. That is why they sell it as rock salt. It usually has a warning on the box about the impurities. I doubt it would kill you but I wouldn't eat it.

          1 Reply
          1. re: Becca Porter
            Eldon Kreider

            OP doesn't sound like someone from the snowy parts of the United States. Huge quantities of rock salt are used to melt ice and snow on roads, etc.

            Rock salt often has some bits of other rock in it. A lot of the rock bits are limestone or other sedimentary rock. The main risk is to your salt grinder or teeth. Paying a wee bit more for kosher salt is a lot cheaper than ruining your grinder or, worse yet, paying for a dental crown.

          2. You can use rock salt to cook (I saw Alton Brown boil fingerling potatoes in water with lots of rock salt but haven't tried it) but I wouldn't put it in a salt grinder. Personally I'd use course sea salt.

            1. No. It is not. It tastes . . . terrible! I had the misfortune of getting some rock salt into my otherwise wonderful oysters on the half shell (sitting on, well you know) and the taste was vile!

              1 Reply
              1. re: willow

                It's bad stuff. And it has big black chunks of stuff in it. I am always surprised at the junk I find in the bottom of my ice cream maker when I dump it out.

              2. I am so glad you posted this question. I have the same issue. I thought rock salt was the right stuff to put in my salt grinder (it's been ages since I've needed to buy some), but when I got the HUGE box home, I realised it was the stuff for snow and ice cream etc

                I am grateful for the answers posted here. Now I know what to do!

                1. This has me wandering if there are different grades of rock salt such as industrial grade and food grade. There are some well known restaurants such as Lawry's which proclaim that their prime rib is roasted in rock salt.

                  1 Reply
                  1. re: Sam D.

                    Yes, I have done the rock salt covered rib roast roast myself years ago on a New Years Eve. As I remember (there was lots of red wine involved) we cooked it at a high temp - buried in the salt, and had to crack it with a hammer, but we then brushed off the salt. Did we injest some salt?, probably, but I think this is vastly different than the op's question of filling her salt grinder with rock salt, which I would NOT do.

                  2. Most rock salt is dirty, filthy stuff. It is mined straight from the grund and is full of impurities such as magnesium and calcium salts, rocks, dirt, etc. and has to refined to become edible salt. It is refined by bringing to solution and recrystalising, either naturally in professional salt beds, which then harvest the white, clean, edible salt, or chemically refined to remove the impurities and add vital nutrients.

                    Don't try eating rock salt intended for salt melting and buy some interesting, large crystal, edible sea salt or refined, edible mined rock salt.

                    1. Does anybody know where to buy rock salt for an ice cream maker? Would kosher salt work just as well?

                      1 Reply
                      1. re: sherry f

                        I have used regular table salt. Morton's makes rock salt and you should be able to find in the grocery store.

                        Don't know why you couldn't use kosher salt. It is the sodium chloride I do believe that helps in the freezing.

                      2. I love the taste of rock salt and I have often used it in soups. However, I recently started to wonder if it was edible, so I wrote to Morton salt, which sells it. They replied to tell me that it is not edible but without specifying what makes it not edible. Certainly there is no warning on the box. I am still using it, but maybe not quite as liberally

                        1. Unless labeled edible, rock salt is not meant for consumption. Same with "ice cream" salt. Your best bet might be coarse kosher salt.

                          1. Apparently there are various grades of rock salt...some edible and some not.
                            Here's a link to some info:


                            1 Reply
                            1. My mother's been using ice cream salt for years in her kimchi...She just noticed today that the label says it's non-edible. She just uses it to brine the cabbage leaves to release water and then rinses it several times after that. Is that ok? Or should she really be using pickling salt?

                              Rock salt is apparently several times less expensive than pickling or kosher salt.

                              8 Replies
                              1. re: soypower

                                Hmm, I just checked my box of Morton's ice cream salt, and it didn't say anything about it not being edible.
                                I agree with those up-thread who say that salt specifically designed to melt snow probably isn't manufactured in a food-grade environment, but I bet ice cream salt is well above something you buy in a 50lb. bag.

                                1. re: gilintx

                                  The amazon website also states the Morton ice cream rock salt is inedible:

                                  "Morton Ice Cream Salt is a non-edible salt ..."


                                  1. re: Chemicalkinetics

                                    Well, heck. I guess I shouldn't have popped a handful of it in my mouth after reading the box. : )

                                    1. re: gilintx

                                      :) It is most likely to be ok.

                                      Why would you pop a "handful" of salt in your mouth (edible or not)?


                                      1. re: Chemicalkinetics

                                        "Handful" was surely an overstatement. Not surprisingly, though, people ask me this question all the time (and not just about crunchy things like rock salt).

                                2. re: soypower

                                  i'll bet hannaone http://www.chow.com/profile/93805 would know about the kimchi issue.

                                  hey, i just looked and hannaone has a website now. (or have i just missed it before?). it is great, hannaone! http://www.hannaone.com/Recipe/note.html

                                  and how do you pronounce hannaone? (in my mind i know that "hanna one" is NOT right! ;-).

                                  1. re: alkapal

                                    han (rhymes with on)na one.

                                    As long as the rock salt is not the kind used for melting ice (or other very high impurity types), using it for salting the leaves should be ok, although a finer salt works better.

                                3. It depends what kind of rock salt you are talking about. If you got a huge bag of rock salt which is for melting ice on the road, then I won't eat it:


                                  The morton ice cream rock salt is also not edible. Here: "Morton Ice Cream Salt is a non-edible salt that can be mixed with ice for making delicious homemade ice cream to rival any ice cream shop. Sprinkle over ice in picnic coolers to rapidly chill canned or bottled beverages."


                                  4 Replies
                                  1. re: Chemicalkinetics

                                    Its not just the impurities in the rock salt. Have you ever seen how it is stored? Big mountains of it....outdoors. Salt is cheap enough. Go with kosher salt. Also, Trader Joes sells these handy little grinders filled with pink Himalayan salt.

                                    1. re: EricMM

                                      Does anyone know what kind of impurities we're talking about? Are we talking little pieces of rock? We're not talking lead or cancer-causing agents, right? If it's just little pieces of inedible rock, no problem, since we're rinsing after brining. Even if it's a little dirt, I'm not concerned. But if it's actually something dangerous, I'd like to know...

                                      And this is in regards to ice cream salt, not sidewalk salt.

                                      1. re: soypower

                                        Potentially metals, such as copper and lead. It would be in trace amounts, but who wants any? Especially if its used regularly? Then there are also the vermin and bird feathers and poop from being stored semi-outdoors.

                                      2. re: EricMM

                                        Excellent points, Eric. I haven't tried the Himalayan salt. Do you know if they are really from Himalayan or they are just saying it. Interestingly, people pay extra for impurities in these Himalayan salt. I think I should try once.

                                    2. Perhaps this answer is begging the obvious, but if you're buying the salt at Home Depot, it's probably not best used to put in your salt grinder. If you're buying it at the neighborhood grocery store in the spice aisle, and it's alongside the kosher salt, you're probably in good shape. A little label reading would also go a long way.

                                      As for what exactly to put into your salt grinder, well, that's a different question. If you use your grinder as a "finishing" touch - that is, you only put it onto some foods after they are plated - then you should consider using high quality mineral salts, like a Himalayan, Hawaiian, or French Fleur de Sel type. They are much deeper than a pure NaCl - they're not as sharp, and can really bring out the flavor in foods, especially on a cut of meat, roasted vegetable, or anything else solid. If you're using it to put into vinaigrette, soup, salt your pasta water, or anything else liquid where the salt just dissolves, then why bother with a salt grinder, and just buy a box of Mortons and a salt pig you can grab pinchfuls from - faster and cheaper. It really depends on what your end use is.

                                      IMO, you only need 3 salts in the kitchen which will cover every need: fine Mortons for baking, course Morton's for adding to any liquid other than baking, and a nice finishing salt in your grinder (or used by hand) for adding to plated dishes (or whole cuts of meat before cutting).

                                      1 Reply
                                      1. re: foreverhungry

                                        Thanks for answering what is not so obvious. There are many forms of salt, some of which are marvelous compounds comprising very toxic elements but are somehow friendly to humans. Any alkaline interacting with any acid will create a salt precipitate, few of which are sufficiently inert for human consumption.
                                        A good rule of thumb: if any item is deposited into a dump truck by a front end loader, don't eat it.