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advice about eating mussels

When I lived in Maine, I was told that you shouldn't eat mussels that don't open when they are cooked, because that indicates that the mussel was dead before it was cooked. My husband disregards this rule, and so far he is still alive. Is this just an old wive's tale or is there good reason to avoid unopened mussels?

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  1. Mussels are cheap, why risk getting sick? Maybe your husband has been lucky and hasn't come across a mussel that hasn't been dead for long but the day he does I'll bet he never eats an unopened mussel again.

    8 Replies
    1. re: KTinNYC

      I second KT, I've always heard that the mussel didn't open because it was dead, and if your hubby eats one that has been dead a while, he may be following up his meal with a trip to the hospital!

      1. re: ideabaker

        Thanks for your replies. The hubby has survived and is still fine (more than 24 hours so far since he ate four of the dead ones), but now maybe he will believe me.

        1. re: henri cat

          btw, it's not just mussels. the rule applies to all bivalves.

          1. re: henri cat

            Ha ha, you have a strong husband :-). Just read that some of the bivalves don't open because the heat wasn't enough to cook them all the way open (strong bivalves?) so that would be another thing to consider, in terms of bacteria...

            1. re: ideabaker

              That's how i tell they are done. As the bivalves (clams, mussels) open I pluck them from the pan. No open, no eat.

            2. re: ideabaker

              I third ... if they don't open they are dead. But he has been lucky. Recently a friend cooked them and he didn't knows about that. He was very sick and ended up in the hospital. He never cooked them before so he just didn't think there was anything wrong.

              Don't take chances as KT said, mussels are cheap

              1. re: ideabaker

                This is a myth. See the article cited way down at the bottom. So much misinformation!

            3. Let me must say that I am one of those people who ate a mussel that didn't open. Once. Once is more than enough. I worshiped the porcelain god for 2 days. Cold sweat, the shakes, along with vomiting as well. I was in bed for 4 days, and really did not feel right for almost 2 weeks. I barely ate anything. My daily diet consisted of a can of Campbells chicken noodle soup, water, and some Gatorade. After about 5 days, I was able to add a grilled cheese sandwich to my daily intake.
              Trust me, if you have ever been sick from mussels, you will remember it. I adore mussels, but did not eat them for 3 years after I got sick. Now I am fanatical about cleaning them properly, and always discard any with broken shells or those that do not open.
              Worst part about this was though I barely ate anything for 2 weeks, I didn't lose one bloody pound. Really, there is no God, is there?

              2 Replies
              1. re: mschow

                mschow, I feel your pain... being sick like that is no joke, especially when you don't even lose a pound after all that effort! Your post is an extra reason why I will continue to skip the unopened bivalves!

                1. re: mschow

                  ... you mentioned paying homage to the porcelain one. I don't think it can grant weight loss wishes, no matter how close it is to the scale.

                2. I've eaten ones that did not open but looked OK. Never had a problem. I'm an aficionado and have gathered and gorged on them on the Maine coast

                  Favorite way to cook is carefully grilled on charcoal to loose as little mussel juice as possible. Dip in olive oil that has had a little salt and cayenne added - And eat

                  1. Apparently your husband loves playing Russian Roulette! The risk is not worth the cost of losing.

                    1 Reply
                    1. re: Caroline1

                      Henri, triple hubbie's life insurance.

                    2. I've heard all those stories about not eating mussels that don't open as they might make you sick. Then I started working in hospitality. The rule in the kitchen is, if they don't open when you cook 'em, open 'em with a knife. If they're look all wrinkly and shriveled they're not safe to eat. If however they are juicy and plump (but the shell just didn't open) they are safe to eat. I've lived by that for years and not once have i been sick (or felt even slightly ill).
                      Happy eating folks.

                      1 Reply
                      1. re: orourkemeister

                        I guess unopened but plump means they are "freshly dead" like in The Princess Bride.

                      2. Adjunct question: Are they definitely dead when they do open? I don't want any surprises and I doubt a living mussel would either.

                        1. Let's not make this an old/young widows tale. Tell him to throw away any unopened mussels.

                          1 Reply
                          1. re: phantomdoc

                            When I order mussels at a restaurant, some of the little guys are loose in the bottom of the serving bowl and for the most part, the shells are wide open, so I assume the mussel got dislodged during the cooking, stirring, seasoning and plating process. But now I wonder about the shells that I've come across that are open about 1/4" and no mussel inside. Could it have been a dead one that fell out after cooking?? How would you ever know if you ate a dead one at a restaurant? I am careful when I cook them myself.....but you never know what you are being served out there in restaurant land.

                          2. The myth seems to have been started by the English food writer, Jane Grigson in her 1973 publication, Fish Book. The exact quote is: "Throw away any mussels that refuse to open."

                            Nick Ruello is a mussel expert and fisheries biologist and he was commissioned to write a report for Seafood Services Australia, on the rather specific topic of adding value to mussels. Along the way, he cooked and ate over 30 batches of mussels, of various sizes, ranging from 21 to 111 mussels.

                            Nick Ruello found he found that some 11.5 per cent of mussels remained closed after a so-called "normal" cooking time. When he forced them open with a knife, every single one was both adequately cooked and safe to eat.


                            3 Replies
                            1. re: Lister of Smeg

                              Lister of Smeg, there is a different take on some of that. To begin with there is a saying the British have that goes back way before 1973, maybe centuries: "Never cook a mussel that is open or eat one that is closed". Of course I was told this after I thought I would surely perish at Heathrow airport. The doctor asked what I had eaten and I told him about the mussels the night before. When he saked if I ate any closed ones I told him I did because they are always the plumpest and he said: "all dead things tend to swell up, don't they?"

                              As for not cooking the open ones, that may not always be the case. I was buying mussels at Pike Place in Seattle and when I kept refusing the open ones the vendor showed me a trick. He used one mussel to peck on the side of an open one and the open one closed. Thus, it was alive and could be bought and cooked. Had it not closed he said he would have thrown it away.

                              I've never again been sick from mussels by following the rule and the advise. But, no matter how good the restaurant or my hostess, I never eat mussels served on the half shell because I can't apply either the rule or the trick.

                              1. re: Barf

                                I have just had the worst time ever,had mussles on wednesday 3rd november asa treat as ive been getting over a kidney infection,by 3am thursday was in agony,so assumed enfection was back.Once at hospital was so sick,never in my life have i been so bad,this went on for hours.In the end the doctor said although i still hada kiney infection this wasnt the problem,he ran a test on my sick yuk,to find it was from eating bad mussles,So after that exsperiance,and i tell you i still feal sick now,i wont risk ordering mussles,i will just cook them at home.

                                1. re: Barf

                                  I didn't know about the shell tapping trick. When I buy them in the sack and sitting on ice at the store, many are open a little bit. When I throw them in a pan of tap water to clean them, I can hear them snapping shut. At that point, I discard any that didn't close up and clean & cook the rest. However, using this method, about half the mussels dislodge from the shell during cooking (my theory is the freshwater shock causes it and I eat them without worry). Maybe 1-2 don't open at all and I discard them.

                              2. As a seafood importer that has been importing a ton of live mussels a week for the last 18 years I can tell you the old adage of not eating cooked mussels that do not open is bunk. It's simply not true. Here are a couple links to Australian articles recently published:



                                2 Replies
                                1. re: SeafoodHK

                                  The study in the ABC article is from 2002 and apparently has never been repeated or peer reviewed. Do you have any other links?


                                  1. re: JuniorBalloon

                                    I don't know about studies as such but if you Google the subject you'll find plenty of people I'm much more concerned about oysters. Even some closed oysters can be dodgy. I've spit plenty of those out.


                                    FYI - Mussels can definitely make you sick. If you cook mussels which are already dead they will make you sick.......and they'll be open.

                                2. i think the dead part depends on how long theyve been dead...obviously ya wouldnt want to eat em if theyd been dead for days or weeks, luckily the shop bought ones are usually only a day traveling away from the boats that caught them but the bigger question is why eat one of natures filtering devices, Im sure too much shell fish in the diet could give you some kind of illness or upset stomach personally I enjoy those small bite sized mussels sprinkled on top of scrambled eggs its bewdiful!! :)

                                  1. This entire thread is kind of silly to me. Obviously there are "old wives tales" in the world then there are things that are based in some form of reality.

                                    From the couple of dozen responses there isn't one person that is ever claiming to have gotten sick from eating only opened muscles, correct? Yes, there are a few claiming to eat or have eaten unopened muscles and have been fine, however in 99% of cases where people get sick it's from eating non-open ones.

                                    Like anything there are several mitigating factors but primarily in my opinion it's the length they have been dead prior to cooking. Also, people might be considering not open one's which do not open widely and still need to be pried open with a fork to get to the meat. If the shell is cracked open at all....if the seal is broken that is considered "open" it doesn't have to be wide open as we are more trained to associate with being properly cooked.

                                    Bottom line to me is simply this.......there are thousands of people who have been struck by lightening and are here to tell the tale about it. Does that mean I'm going to walk through a thunderstorm holding an open umbrella.......NO!

                                    1 Reply
                                    1. re: jrvedivici

                                      I think your logic is a bit flawed. Perhaps persons don't report getting ill after eating opened mussels because, per the old wive's tale, they've no reason to associate eating open mussels with later gastro-distress. Or perhaps this happens so infrequently that the reports are too few and far-between to get noticed.

                                      As to the discomfort suffered by those who have eaten unopened mussels, I suspect that certain individuals are allergic to shellfish of different types and it is their allegric reactions that they are experiencing, depending on their own internal chemical conditions at the time.

                                      Dead men tell no tales, true, but so far no living person here has reported an actual death due to eating a closed mussel, only rumors of such an outcome.

                                      Deaths by shellfish are attributed to toxins produced by decomposition or ingestion by the shellfish of toxins like sewage or chemical outflows, and red algae. This seems unassociated with the open or shut condition of the affected shellfish, though it's always possible. Just not probable.

                                    2. It depends on how long the mussel has been dead and which bacteria have made the corpse their home and food supply. I'd rather not find out.

                                      1. Regarding mussels, it's a myth, an old wives' tale. See this article from the Australian Broadcasting Commission, for specific advice:


                                        Summary: Dangerous mussels smell bad. The most dangerous will be among those whose shells open early, before they've had time to cook away pathogens.

                                        Mussels shells' opening or closing have to do with heat's effect on the muscle tissue holding the shell together, nothing to do with a mussel's safe edibility.

                                        2 Replies
                                        1. re: KingNeptune

                                          I was all ready to find evidence and tear this apart but I think the evidence suggests it might be right. See here for a nice treatment of the question: http://www.culinarylore.com/food-hist...

                                          If you think about it why would a supposedly already-dead mussel fail to open? The opening occurs when the heat denatures the proteins in the adductor muscle that hold the clam shut. Per that link James Peterson recommends cooking closed mussels and forcing them open to check for mud if they stay closed. If they look/smell/feel ok he suggests eating them.

                                          1. re: KingNeptune

                                            Myth or not, but seeing as so few don't open, I'll stick with the old wives' tale. And so will my old wife.

                                          2. I can not say for sure, however I have just spent the last 72 hours being VERY sick from eating a mussel that did not fully open up. I had so many in the bowl at a good restaurant that I thought I might eat just one that had
                                            partially opened. It did not tast exactly right but I soaked the break in the fluid and soaked out the tast. WRONG111 I will probably never eat mussels again since it has occurred to me that if they are partially open, and dead, is the juice from inside that partially opened mussel mixing in with the wonderful tasting juices that are there to dip in. Good luck if you keep eating them.

                                            1. To add to the other comments, mussels of all shellfish can make you sicker than most others if you hit a bad one, even l who have cheeses older than my grandchildren do not eat an unopened mussel.

                                              2 Replies
                                              1. re: Delucacheesemonger

                                                Everyone seems to be hung up on unopened mussels - like they're the only ones that can make you sick.

                                                Again - take this from somebody that sells a ton of mussels a week. All the mussels that we know have died - are open.

                                                If they're not - we don't know they're dead. Unless you've personally inspected them - pulled their beards to see if they react you won't know. If you're eating them in somebody else's home, at a hotel, in a restaurant there is no guarantee the open mussel you're eating was alive when it was cooked. Your nose and your taste buds are going to tell you if it's okay or not.

                                                I still think that a closed mussel isn't a definitive indication of anything.

                                                1. re: SeafoodHK

                                                  I collect wild 'blue' mussels. When I remove them from the rocks I gently tap them. If the shells don't contract I do not take them home.
                                                  If the fish monger won't let you tap the mussels do not buy them.
                                                  Do not soak the mussels in fresh water. You'll kill the weak ones and end up with a pot of dead or dying mussels.
                                                  NEVER 'boil' or steam sauté the mussels together. If there's a dead one in the bunch you are basically spreading any pathogens around in the water.
                                                  I use a large steamer basket to cook mussels and oysters. I NEVER use the liquor.
                                                  Otherwise I grill them.
                                                  Simple question: You have fifty mussels you bought some where. You throw them in boiling salted water. They cook for as long as it takes for them to open. You remove them and notice three of the fifty did not open. Why on earth would any one even consider eating the three that didn't open........FOR ANY REASON!??????
                                                  I have fifty chickens and it's time to take them to the processor. Three of the chickens ain't looking so good. They are sort of flopping over on their sides. That's OK. I'll put them in with the other chickens. Then when I start eating them chickens I'll never know if the one in the pot was one of those 'floppers'. "Never had a bad chicken yet".