Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Meat made from recycled carbon dioxide

neo.life

Post reply on HN
Print view View original

41–50 of 178 posts

Re: Meat made from recycled carbon dioxide

#41

Post by dqv »

asdff wrote: post #38
whimsicalism wrote: post #26

Earlier quoted context omitted.

Meat production is not carbon sequestering, it is carbon emitting. Most agriculture in general involves replacing more carbon sequestering natural growth with agricultural fields.

I think that would depends on what the natural growth is actually able to sequester, no? Not all areas clearcut for farmland were lush, quite the opposite actually with artificial irrigation bringing in the possibility of generating all that biomass.

No, meat production is still carbon emitting. What you’re thinking of is having cows manage land. For that to sequester carbon, you have to keep the cows alive and not be in a constant consume-supply cycle.

Re: Meat made from recycled carbon dioxide

#42

Post by throwawaymaths »

usrn wrote: post #10
elil17 wrote: post #5

I recently spoke with a researcher working in this field. She identified three key issues: 1. Doing it with microbes means keeping the microbes alive, which is hard. You need to essentially replicate the functions of an animal, and you’re not necessarily going to be more efficient at them. 2. You can solve this by just doing it in a chemical process with catalysts and stuff. This is pretty easy except we have no way…

You can go half way and just use micro organisms like algae. Those are very easy to keep alive, they really just need sun and CO2. Then you can use the sugars and lipids as feed stock for the next step.

Algae are not that easy to keep alive, unless you are skimming a wild pond, or harvesting kelp or something. At that point you might as well get your sugars from conventionally farmed plants.

Re: Meat made from recycled carbon dioxide

#44

Post by pxeger1 »

ravenstine wrote: post #35
howlin wrote: post #11

Instead of elaborate carbon capture infrastructure, it seems more straightforward to just use photosynthetic organisms like algae. Either engineer algae to make the proteins you want, or engineer yeast or some other microbe that can take the products of algae and convert to these proteins. Honestly it sounds like a needless and impractical gimmick.

Or we can just have plants capture the CO2, give those plants to large ruminants which will feed those plants to the microbiota in their cecum, digest the microbiota and converting it into the kind of nutritious protein and fat that hominids have adapted to digest almost exclusively for millions of years. If one is worried about the methane emissions of cattle, it's not really clear that this is even a secondary conc…

Meat farming takes in CO2 (photosynthesis), and produces CO2 (cows breathing) and CH4 (cows farting). CH4 is a much more potent greenhouse gas than CO2, so, even by your flawed simplified model, farming cows has a net negative greenhouse effect.

Re: Meat made from recycled carbon dioxide

#45

Post by adrian_b »

photochemsyn wrote: post #14

This is absolutely a 'do not trust these claims without seeing peer-reviewed publication in a reputable journal' territory. For one thing, this is likely to be a slow method of capturing CO2 (H2-powered CO2-capture metabolism, called 'chemoautotrophy' is almost certainly going to be much slower than green plant photosynthetic capture rates). Maybe you could speed it up by adding enough hydrogen at optimal rates, but…

They appear to have given very vague information about what kind of bacteria they culture.

Assuming that they have told the truth and they feed their bacteria with carbon dioxide, dihydrogen and dioxygen, then those bacteria are not powered by the H2 with CO2 reaction (which is possible only in anaerobic conditions, by acetogenic or methanogenic bacteria/archaea), but by the oxidation of hydrogen.

The use of the word "fermentation" is completely inappropriate. Regardless what kind of bacteria they are using, the bacteria do not carry out any kind of fermentation (which refers to obtaining energy from large molecules, either by converting them into isomers or by breaking them down into smaller molecules).

In any case slowness is not their problem, because they do not use air as the source of CO2, but they use concentrated CO2, which accelerates a lot the CO2 capture.

Also, if the bacteria oxidize dihydrogen, they dispose of much more energy than the anaerobic bacteria which also capture CO2, so a doubling time of a few hours is believable.

What is unlikely is that they can produce their proteins at a cost comparable with, e.g., chicken meat or proteins extracted from legumes, when they use relatively expensive concentrated CO2 and dihydrogen to feed the bacteria and also a presumably expensive process to separate the protein and convert it into a product resembling meat.

Re: Meat made from recycled carbon dioxide

#46

Post by aszantu »

azakai wrote: post #33
manigandham wrote: post #28

Earlier quoted context omitted.

There’s nothing simple about changing human nature. If you have to start with "if people would just choose" then it's not viable.

It's not simple, you're right, but history has shown again and again that it can be viable. Society has made a lot of progress. In the end people can just choose. If someone reading this right now eats meat, then you can make the choice to eat more plants. Please do so as much as you can, that will make a difference in saving the planet!

I'd love to eat plants a lot. Just turns out they give me depression.(takes about 4 days after ingestion)

There is something called bio-availability and there are nutrients in meat that you don't ever get from plants.

But it would be nice if there were public pig pens where you could recycle food waste into bacon.

Transportation is the biggest co2 producer...

Re: Meat made from recycled carbon dioxide

#47

Post by ravenstine »

pxeger1 wrote: post #44
ravenstine wrote: post #35

Earlier quoted context omitted.

Or we can just have plants capture the CO2, give those plants to large ruminants which will feed those plants to the microbiota in their cecum, digest the microbiota and converting it into the kind of nutritious protein and fat that hominids have adapted to digest almost exclusively for millions of years. If one is worried about the methane emissions of cattle, it's not really clear that this is even a secondary conc…

Meat farming takes in CO2 (photosynthesis), and produces CO2 (cows breathing) and CH4 (cows farting). CH4 is a much more potent greenhouse gas than CO2, so, even by your flawed simplified model, farming cows has a net negative greenhouse effect.

So what if methane is more "potent"? How potent and in relation to what, and in what amount?

Large ruminants and other animals that produce methane roamed the Earth in greater numbers long before humans came up with the concept of livestock. Stable isotopes of carbon in atmospheric methane don't support livestock being a contributor to rising methane at all. Because livestock methane is part of the carbon cycle, and livestock aren't in greater numbers, problematic increases in atmospheric methane have to be coming from somewhere else, most likely things such as fracking. Carbon-14 would be increasing in the atmosphere if cows were responsible.

Even if we eliminated meat consumption, hypothetically speaking, it's totally unclear and unfounded that any meaningful difference would be made. According to the United States EPA, agriculture as a whole makes up 11% of greenhouse gas emissions in the United States. That percentage includes everything from farm to table, meaning that cows in particular make up a fraction of that since most of the greenhouse gas will inevitably come from transportation and processing. Methane itself makes up ~11% of greenhouse gas. Show me any evidence whatsoever that correcting for the greenhouse gas from animals bred for food will make any appreciable difference in changing the climate in the favor of humans.

By the way, most of the methane from cows comes from their burping, not farting.

Re: Meat made from recycled carbon dioxide

#48

Post by sokoloff »

issa wrote: post #25

It is pretty insane when you think about it. We could get all the climate harm reduction benefits the article mentions if people would just choose to eat plants instead. Seems like a very simple solution.

We wouldn’t have had to invent different forms of birth control if people would just refrain from penile-vaginal intercourse unless seeking pregnancy. Seems like an equally simple solution.

Re: Meat made from recycled carbon dioxide

#49

Post by albertgoeswoof »

aszantu wrote: post #46
azakai wrote: post #33

Earlier quoted context omitted.

It's not simple, you're right, but history has shown again and again that it can be viable. Society has made a lot of progress. In the end people can just choose. If someone reading this right now eats meat, then you can make the choice to eat more plants. Please do so as much as you can, that will make a difference in saving the planet!

I'd love to eat plants a lot. Just turns out they give me depression.(takes about 4 days after ingestion) There is something called bio-availability and there are nutrients in meat that you don't ever get from plants. But it would be nice if there were public pig pens where you could recycle food waste into bacon. Transportation is the biggest co2 producer...

You switched to a plant based diet and it gave you depression 4 days later?

Or you only eat meat and tried eating fruit and veg with it?

If it’s the latter, I don’t think it’s the plants causing the problem!

Re: Meat made from recycled carbon dioxide

#50

Post by IanCal »

ravenstine wrote: post #47
pxeger1 wrote: post #44

Earlier quoted context omitted.

Meat farming takes in CO2 (photosynthesis), and produces CO2 (cows breathing) and CH4 (cows farting). CH4 is a much more potent greenhouse gas than CO2, so, even by your flawed simplified model, farming cows has a net negative greenhouse effect.

So what if methane is more "potent"? How potent and in relation to what, and in what amount? Large ruminants and other animals that produce methane roamed the Earth in greater numbers long before humans came up with the concept of livestock. Stable isotopes of carbon in atmospheric methane don't support livestock being a contributor to rising methane at all . Because livestock methane is part of the carbon cycle , an…

> So what if methane is more "potent"?

If you are concerned about global warming, swapping one thing for something else that has a greater negative impact is bad.

Having a process or animal that converts CO2 to methane is not neutral just because the CO2 was already in the atmosphere.

> How potent

25x more.

> and in relation to what,

CO2 over a period of 100 years usually.

> and in what amount?

Any amount, it's a relative figure.

Post reply on HN