Yes. Explanation after the photo...

The question comes up occasionally whether it's okay to eat unopened mussels or not. A few years back, Nick Ruello was commissioned by the Australian mussel industry to answer that and other muscular questions.

Nick tracked the commonly accepted theory to an English cookbook by Jane Grigson from 1975. At the time, some European mussels were being dredged from polluted beds. By the 80s, pretty much every cookbook and magazine gave the same advice- you should not eat any shellfish that don't open when cooked.

Over the course of his study, Nick bought, cooked, and ate bags of mussels. 11.5% of the cooked mussels did not open even after prolonged cooking and the flesh became overcooked. He also ate these unopened mussels and over the course of the study did not become sick. Here's his advice for responsibly farmed mussels:

Before cooking, tap the mussel and see if it closes. If it doesn't close, smell it. If it smells bad, throw it out. If it doesn't smell, it has only very recently died and is safe to eat. To make sure that all mussels cook thoroughly, don't put more than two layers of them in a pan at the same time. If you're in a restaurant and just one mussel smells "off," it could unfortunately taint the entire bowl so you should feel free to send them back.

We get our mussels from Carlsbad Aqua Farm. Here's a video on how Carlsbad Aqua Farm operates so you can see what rigorous practices they follow to ensure healthy shellfish.

So next time you see one of the 11.5% of unopened mussel on your plate, that doesn't mean it's bad. It just means that the mussel didn't release its abductor. Open it up and enjoy!