As the summer draws to a close, we re-enter mussel season. Although mussels are one of the most sustainable forms of seafood, you should avoid harvesting them between May and August as this is their breeding season.
Make sure you collect more mature mussels of at least 50mm in length as smaller ones are less good to eat. It's worth studying the tides to get to the beach for a low Spring tide as this is when you'll find the biggest juiciest mussels. Avoid picking any mussels with a damaged shell - you want to be sure they are alive and fresh. Ideally take a bucket and bring your mussels home in clean seawater. Otherwise use a carrier bag and try to keep them cool.
Once you have harvested your mussels, soak them for a few hours somewhere cool in clean saltwater to allow them to purge any sand (don't submerge them in freshwater as this will kill them). If you don't have seawater, you can use cooking salt in tap water at the ratio of 32 grammes per litre. Sort through them, tapping any that are open on a surface to see if they close shut. Discard any that remain open, or any that are damaged (they have perished and are not safe to eat). Mussels must be thoroughly cleaned and rinsed before cooking. The "beard" (threads that secure the mussel to the rock) must be removed. This can be done by giving the beard a forceful tug with your fingers and pulling it away or by cutting it off with a small and sharp knife. Scrape any barnacles off using the back of a knife. Rinse several times to remove all traces of sand. Cook according to the recipe; discard any that are still shut after cooking.
There are plenty of mussel recipes on the internet. As a rule of thumb they go well with garlic, white wine, lemon and chilli and work well alongside smoked fish. We often grill them Croatian-style with garlic and a salty cheese, which makes a nice starter. We also tried smoking some with some bay leaves in the chimnea and they were very nice, particularly with a bit of lemon and chilli.
Some suggestions for foraging walks
Tregardock beach has some good mussels, particularly on low spring tides. It's worth walking along the beach first to find which rocks have the largest mussels as they vary quite a bit. There isn't much parking at Tregardock so if you're going at a busy time (e.g. on a Bank Holiday), you can park at Trewarmett and walk across the fields.
Near Polzeath, Lundy Bay has loads of mussels, but a lot of them are small. However there are some that are reasonable-sized on the far sides of the beach at low tide.
Trebarwith Strand near Tintagel also has lots of mussels. Most are small but at the very lowest point of the tide, you can walk across to Hole Beach and there are some bigger ones at that end of the beach.
Towards Newquay, at low tide you can walk 2 miles of beach from Watergate Bay to Whipsiddery and even combine with a meal at Jamie Oliver's Fifteen or the Mermaid Inn at Porth. The best spots are around Zacry's Island and on the far side of Whipsiddery.
If you're REALLY keen to get big mussels, bring a wetsuit, fins and a snorkel as below the low-tide line the mussels are MASSIVE. The sea is still pretty warm in September and October so this isn't quite as crazy as it sounds. Some kind of fins are strongly recommended as there are strong currents on many beaches and without fins, you may not be able to outswim them.