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Comment by NickM | Hacker News Reader

So it's nice to think that maybe this could work to turn food waste back into edible protein, but is this actually more efficient than just composting the waste and using it to grow crops? Sure, maybe this is a good source of protein, but so are, say, beans, right?

I would hazard a guess that for most western cultures, it's probably easier to convince people to replace meat with plant-based food than it is to replace meat with bugs. So if we want insect-based foods to take off, I feel like there's got to be some fundamental advantage over just switching to a vegetarian diet. Maybe that advantage exists; I just don't know what it might be.

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"So it's nice to think that maybe this could work to turn food waste back into edible protein, but is this actually more efficient than just composting the waste and using it to grow crops? Sure, maybe this is a good source of protein, but so are, say, beans, right?"

The reason that I am currently (as in, right now) building a soldier fly breeding box to mass produce these larvae is that the exit ramp of the box goes directly into the chicken run.

The conversation that spurred this was a thought experiment wherein a friend and I wondered how we might keep our flocks going in the absence of chicken feed available for purchase.

It's easy for him: He lives on many acres of flat, tillable land in Minnesota - if he wants his chicken flock to be self-sufficient he can just grow and harvest corn.

Our ranch is in Marin County, however, and while I have more than double the amount of land he does, very, very little of it is flat and almost zero is tillable. We're not going to take the precious 2-3 acres of flat land we have and grow corn in rows on it.

Hence the soldier fly larvae breeding operation.

As for efficiency, we are converting food scraps to larvae to chicken eggs. So the original input is "free" but there are then two animal conversions involved to produce the chicken egg since we have no intention of eating the larvae themselves.

Here's a DIY Black Soldier Fly Composter with an Automatic Chicken Feeder

https://gardenpool.org/beneficial-insects/black-soldier-fly-...

By running it through two species, especially one that is a scavenger, you are also reducing the pathogen load.

Composing fatty and high protein waste can be difficult, if for no other reason than it attracts vermin. I think that's one of the areas Black Solider fly larve excel.

Realistically, using them as a food source for farmed fish and poultry is much more likely. Although obviously less efficient in a gram for gram basis.

The added efficiencies in composting could also help solve the massive problems with monoculture farming. Imagine this approach for replenishing the nutrients in an acre of overused farmland:

1. Container full of food scraps, bio waste, and carbon scraps arrive from city, get spread over fallow land

2. Maggots are released, reproduce, ingest meat scraps

3. Chickens are introduced into environment, eat maggots and larger scraps, release compost as manure and scratched bedding

4. Remaining maggots and waste is collected, maybe dumped to tilapia or pigs

5. Replenished field is plowed for cash crop, nitrogen releasers, or untouched for a season to allow grasses to grow as grazing land

EDIT: Admission time - I wrote this article before reading the article about the maggot cultivating process. I'm just a little passionate about armchair-ecology. Maybe this process could be completed in a mobile facility that moves from acre to acre on a monthly basis?

From TFA:

> An acre of land used to raise soldier fly colonies can produce more than 60,000kg of protein per year, according to various peer-reviewed estimates. That’s several orders of magnitude greater than the per-acre protein yield of cattle (about 18kg), soybeans (430kg) or chickens (816kg).

At least from a land density POV, it wins hand over fist.

Probably not the full story. What do these bugs need for food? Plants take in water, micronutrients, air, and sunlight.

They eat the organic waste

So in order for us to farm these flies, they need organic food. So we're back to growing food for our food, just like we do for livestock.

Yes, but the protein conversion factor is orders of magnitude better.

The examples given in the article are difficult to dispose of waste products from other food industries such as brewing. We're already making beer. Might as well use the waste products for something productive.

It's not easy to convert waste to a commodity. Recycling has a big problem with this - if the waste isn't provided in the right way, then it's totally useless (ie. plastics need to be completely clean, all food waste has to be washed out, otherwise it just goes to the landfill).

What if different breweries output different quality waste? Some is too watery, some too thick. Is it now worth it to reprocess this waste to make it usable? Is the collection and processing of this waste cheaper than just growing food for the flies?

The article makes it pretty clear that the soldier flies aren't fussy at all:

“They’re generalists,” Tomberlin says, and eat just about anything. Pig manure? Check. Human waste? Check. Food scraps? Check. The only organic materials they haven’t had luck with are bones, hair and pineapple rinds, he says.

>It's not easy to convert waste to a commodity. Recycling has a big problem with this - if the waste isn't provided in the right way, then it's totally useless (ie. plastics need to be completely clean, all food waste has to be washed out, otherwise it just goes to the landfill).

We need to acknowledge that the requirements of 'almost-perfection' required in our recycling stream is something we built into it. We had reusable systems that operated without issue for decades that we discarded in favor of modern co-mingled recycling (which is obviously failing us). There's no rule of recycling or reusing that says the parent material needs to be pristine in its condition to be recycled, thats a rule we introduced because of how 'we' thought to do recycling. We could build re-usability back into our systems, we are choosing not to do so.

For these maggots, our waste is it's fuel. Biology's produced a whole bunch of bizarre, extremely niche DNA coded self replicating machines. If the machinery is already there, and the ethical concerns are minimal, why not exploit them?

How scalable is this then? What happens if the local breweries can only supply 50% of the waste demand for the larvae?

What if it's not 50% but only 10%? How do you feed the insects then?

The difference is that we're using stuff that's already being grown. It's re-using that which already exists. This could be lawn clippings, coffee grounds, or other compost stuff. It could be rotten food and help solve the food waste problem. We're not growing more food, we're making wasted protein available.

They are also great animal feed. Chickens and fish find them irresistible

Sooo... you should get more than 816 kg of chicken per year, clearly.

We call it “chicken crack” where I live. It’s a blast going out to the flock with a bucket of these.

Compost is microbe and invertebrate poop with some indigestible bits mixed in.

BSFs are going to create castings as well. In a large operation you probably get both.

Agree. I don’t get it. Plants fill the protein need without the need for bugs. Bug protein seems like a solution in search of a problem.

Aren't plants not very protein-dense?

Is that really a problem? People tend to vastly overestimate our protein needs.

Whether that matters depends on whether people are eating enough protein. A cursory search shows that most people in the west vastly overeat protein beyond their needs. Yet aggressive marketing has Americans thinking they need more protein.

20g of protein in a cup of cooked lentils sounds pretty adequate to me. At 180lbs, it's only recommended that I get 63g of protein. It's not a challenge. I get almost half that in a single lentil salad including any other plant matter I toss in there with its own amino acid profile.

Maybe so, but Americans are also some of the tallest people (especially compared to those who eat much less). I'm not saying this is necessarily for the better or for the worse, but it's not easy to just say "you should eat this". Recommendations for diet change - remember when it was "don't eat fat", then "don't eat sugar", then "don't eat either"? Who knows.

After all the diet recommendations and panics about obesity, I still think most of us know what healthy eating is.

I heard somewhere that anybody 6’ tall or above has back problems. Anecdotally, this seems plausible enough to me.

Meanwhile there’s been a decades long marketing campaign to sell people on eating all the animal fat and protein they want with the dubious promise of weight loss and that always being healthy. Also decades long increases in cardiovascular diseases and death.

I'm over 6' tall, upper 30s age, and have never had a back problem. I also squat and deadlift frequently, which a lot of people don't do.

USA, just cherry-picking the non-hispanic whites, isn't even in the top 25 of average height, height is hereditary, meanwhile USA is known for catastrophic eating habits that I find hard to spin in a positive way.

Are you sure that was the evidence you wanted?

You can make plant based foods arbitrarily protein dense with things like gluten/seitan and nutritional yeast.

Many beans and lentils are protein dense. For example, Soybeans have more protein than chicken.

Dried beans have more protein than chicken, not cooked beans though. I could say that dried chicken jerky has more protein than dried soybeans if you are disregarding water content as it contributes to weight.

oh, interesting. Thanks for the heads up.

Take a look at the nutritional information for tempeh though.

Protein isn't monolithic: there are 20 amino acids which are found in different proportions.

Plants, specifically, often have less leucine than animals, which is an important signalling molecule that feeds into mTOR as well as protein synthesis regulation.

https://www.physiology.org/doi/full/10.1152/ajpendo.00153.20... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3322509/

This doesn't make plant protein 'bad', but it is something to consider, especially if using a plant-based diet.

> but so are, say, beans, right?

Beans (and other non-animal) proteins are not "complete", meaning they lack certain things that the human body needs to be healthy.

Edit: For those saying it's untrue, the research has been done to prove it. Of course, you're free to deny any research and reach your own conclusions, but that doesn't make it untrue.

Edit 2: I just stated a fact in answer to a question. I did not provide any context, such as individual eating habits, beyond what was implied by the question. The fact is that bean proteins are not as good for us as animal proteins when compared directly.

That's not true, at least for humans.

On a related note, I came across Nixtamalization recently. It's one of those stories reminiscent how the Royal Navy managed to 'forget' the cure for scurvy. It had been practiced for thousands of years in South America but when the western countries discovered maize they didn't understand why. Turns out it's responsible for making maize a complete protein source.

https://en.wikipedia.org/wiki/Nixtamalization

Even if that were true, presumably people eat more in a week than one type of bean for every meal.

You're basically suggesting that people need to vary their diet with at least two things instead of one thing. I don't know anyone who struggles with that except maybe poor uni kids where eating beans would likely be an upgrade to their normal cuisine.

While this is technically true, it's not a problem for 99.9% of people. If you are eating any kind of varied diet, you'll be fine. The only people that might have a problem are people who only eat 1 thing.

From the article: "In one year, a single acre of black soldier fly larvae can produce more protein than 3,000 acres of cattle or 130 acres of soybeans"

Compost costs ~$50/ton vs fish meal (a comparable protein BSF is trying to displace) costs ~$1,500/ton. Why? Compost is a very low level of organization, whereas protein is a very high level of organization.

Could be used to feed animals!

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