Are Naked Clams the future of food?

We saw a story about a Naked Clam and thought it would be remiss of us Naked Scientists not to “cover” it. The researchers have been developing a way to grow these bizarre organisms, which can apparently eat their way through an oak beam and sink a ship in under 9 months, as a possible source of food. They’ve also been using artificial intelligence to analyse social media to explore the appetite consumers might have towards eating these bivalves. Supposedly, they’re delicious, and most people decide they like them! Cambridge University’s David Willer explains more…

David - Something sunk Columbus' ships when he was sail around the Caribbean in the 1600. And that something is actually a type of clam, which instead of having a shell eats and burrows into wood. These things can reach up to two metres in length. They're huge. We dub this 'the naked clam', also Teredinids that's the kind of scientific name.

Chris - When you say they're naked, that's no shell whatsoever? So are they a clam that's lost their shell at some point then, or did they just never have one? Are they the sort of clam equivalent of a slug versus a snail?

David - Take Nearly Headless Nick from Harry Potter. They've nearly lost their shell. But what's actually happened is the shells evolved into two big boring drills which allowed them to drill into the wood and actually inspired the drilling machines for the channel tunnel.

Chris - Where did they actually come from then, because obviously ships are a fairly recent phenomenon, did they eat wood that fell in the sea then? Is that where they would've evolved this behaviour?

David - Naked clams naturally would consume wood degrading in the sea. They're often found in mangroves actually, where they'll eat mangrove wood. So if you go out to the Philippines or Thailand, you will find people who've consumed them for thousands of years and harvested them from the mangroves.

Chris - Wow. And what was the question you wanted to know about them, apart from the fact that they look like they sank Columbus' ships?

David - Well, the key thing is that recently we designed the world's first lab scale naked clam aquaculture system. But any new food solution is useless if no one's actually going to eat the animals. So we wanted to understand, are people going to eat a naked clam and will they enjoy the taste of it?

Chris - First of all, tell me what does that aquaculture system involve? You basically just chuck bits of wood in a swimming pool and they grow. Is that the idea?

David - Our concept is actually something like a shipping container when we scale it up, where you put wood in, you farm the naked clams, and you get a nutrient packed protein source coming out the other end.

Chris - So you just eat the clam, that's the idea. Or do you turn them into something else?

David - You can eat the clam or you could process it into fish fingers or fish cakes.

Chris - And what does it taste like?

David - They taste like oysters. But, like a whiskey tastes a bit like the wood you've held it in, The flavour of a naked clam is influenced by the wood you grow it in. So something grown in oak is different to something grown in teak or something grown in pine.

Chris - Now two of those woods are hard and valuable. Pine's a bit cheaper. Is this something we could do sustainably?

David - Our concept aims to use waste wood from the forestry industry, so the kind of chippings off the forest floor. And we're working with pine at the moment.

Chris - Okay. So how does this actually work then? I know you said you've got a shipping container, but what's the throughput? How long do they take to rear? Is this actually practical?

David - Currently we're running a lot of scale up work in our labs. We're targeting a six month production cycle. So six months from, from your juvenile to a larger individual, around 30 centimetres in length.

Chris - That's quite fast growth.

David - It is fast growth. They are the world's fastest growing bivalves. There is a lack of data on that. We are trying to get some really good numbers on that data.

Chris - And are they good for you? As in, do they contain various nutrients that, if you eat this, you're not having to eat salmon and so on because you want some oily fish and so on. Can they substitute for other rarer things that we're currently decimating the oceans to get?

David - They are nutrient rich. We've done the world's first nutrition analysis on them. They've got more B12 than muscles, which already are renowned as a B12 source. They're high in protein, and because they feed on algae too, you can fortify them with extra Omega-3 by providing them with algae. But it only works if people eat them.

Chris - And what does the research suggest and how did you do that to find out?

David - We decided to leverage AI. It's a hot topic, but actually it can be really useful. And what we did is we analysed all the videos and comments and likes across the big social media platforms. And what we found was really interesting. Whilst before trying naked clams, it was about 50/50; half of people thought they liked them, half people thought they wouldn't like them. Once people had tried them, about 84% of people liked naked clams. And that's really key because that tells us that if you can get people to overcome that initial hurdle of trying a new sustainable food, it can go a long way to driving change.

Chris - Were these ate raw? I mean, how do you prepare them and do you think you're looking at a subgroup of people who are ambitious and willing to try something a bit novel and your average person, if you went to an average person in the street with a plate of these things, they would just say no thanks.

David - So there were a variety of recipes ranging from raw to naked clams, battered a bit like calamari, to marinated dishes and stews and curries. So a big variety of dishes which do suit a variety of tastes. One thing worth adding in is that we did get the Financial Times actually to pull together a set of recipes and we got one of them cooked out in the Philippines by my student's mum, who cooks them regularly for dinner. That was fantastic, you know, tasted lovely.

Chris - And one other practical question. When we try and do mass scale production of this kind of thing, we force lots of animals to grow in a small space. It's intensification, isn't it? Inevitably diseases emerge, parasites creep in, viruses crop up that can begin to decimate crops and so on. How do you keep them safe so they don't succumb to those kinds of threats?

David - The key thing here is controlling the colonisation of the wood. If you have lots of larvae in a tank, colonising wood, you want to ensure a certain number settles. And that's where actually the wood matrix design we've got for farming them is so important. So it's a patent pending system which ensures you just get a small number of individuals colonising the wood, so you get fewer big individuals rather than an over colonisation.