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South Korea now recycles 95% of its food waste (weforum.org)
538 points by okket on Apr 13, 2019 | hide | past | favorite | 163 comments

Norway: 50% of food, 77% of energy in waste, and 97% of toxic waste is recycled. https://translate.googleusercontent.com/translate_c?depth=1&...

We are also rebuilding some of our plants to sort waste with machine learning. The initial tests are really promising. Several of them are already sorting out most plastic using spectrometer-sensors, so we don’t need to do it manually. In combination with the machine learning the tests get it up to 99.9% or higher. https://translate.googleusercontent.com/translate_c?depth=1&...

Once upon a time I came across AMP Robotics[0], a company that also uses ML and robotics for sorting waste. Pretty nifty project, in case you're curious. You can see the robots in action on their website[1]


0. https://www.amprobotics.com/

1. https://www.amprobotics.com/amp-cortex

Sorting trash maybe useful but sorting Legos is where it’s at!


Recycling doesn't help much as long as Norwegians throw away 40-50 kg of food per person each year. :(

That's less than a kilo a week, say 120 g per person per day.

In my household I suspect that most of that is potato peelings, onion skins, orange, apple, and banana peel, teabags, etc.

If you drink tea five times a day you have 10 g of teabags.

So, what is the definition of food waste? If it is food that could be eaten then in my household of four people it is very close to zero. But still the kitchen compost bin is always full.

Coffee drinking adds up too. 3 coffees per day, 20g per coffee. Once you add in the extra coffee at weekends and visitors, it’s 30+ kgs of grounds per year. The garden seem to like them though.

> If you drink tea five times a day you have 10 g of teabags.

Who drinks tea five times a day??

Good point - it's an entirely unrealistic number. It's just hit 1pm and I'm on my 6th already.

You are clearly not from the UK! I know lot's of people who have 8-12 cups of tea a day (this is on the higher end, but not super unusual...)

Or Russia, or India, or...

Lots of people.

A fairly large portion of the world’s population?

Vs how much per capita for other countries?

Is that as a result of overproduction or just wastefulness?

At every point in the supply chain (grow, pick, sort, package, deliver...) a % of produce becomes more expensive to keep than to throw. So it being dropped.

I'd think that most such waste are still used efficiently. They may not be fit for the stresses of being shipped and stored the full distance to the supermarket and in your home, but much can still be used for animal feed and compost.

Right. Also, there are plenty of other uses of vegetable (by which I mean all non-animal, not just veggies) waste matter too, uses of all kinds, including industrial, home, medical, etc. Just randomly check out say Wikipedia articles for 10-20 common vegetable matter sources, such as corn, coconuts, bananas, soy(a)beans, guar, etc., to get a better idea about this.

Is that not overproduction in a sense?

Food shortages are really really bad even for small amount of time which is why food is over produced in excess.

Not exactly. For example, if you have a picker machine harvesting 80% of crop, and manual work ain't cheap (it's Norway), you'd probably throw 20%. But you can't "ungrow" it in any meaningful sense. Agriculture is complex.

One "solution":

Invite people to come down to hand-harvest the rest of it. Charge them a nominal fee (if at all).

Yes that is what we do here. It’s inspiring but the impact on food waste is negligible.

This sounds more wasteful to me. In terms of manpower and cost of commute.

If it's cheaper for that person to commute in order to eat then it's probably less wasteful from a financial perspective at least. Definitely possible to be even less wasteful of course, but I think without perfect weather and population models (which will never truly exist) it'll be hard to eliminate waste to a certain extent.

Something like this is usually not done out of economic incentives, but because of ethical and emotional incentives. In the end people do it to feel good, but might do more harm, just in another way.

This is true. Often times it is tilled back into the ground. Food Banks get this produce for free(less the cost of packing and shipping)

Shouldn’t that be exported to underfed populations?

At what energy cost?

Donating your overproduced (and likely subsidized) food to poorer countries also disincentivizes food production there, thereby perpetuating the food shortage problem.


That Europe push technology, not people to solve the recycle problem?

>The bag charges also meet 60% of the cost of running the scheme

Recycling metals is substantially profitable, because scrap metal is actually worth something. Making new metal from old metal requires far less energy than making new metals from raw ore, even factoring in the costs of transportation and processing.

Does collecting and composting food waste actually result in a net reduction of our use of finite resources, or is it just a sop to make us feel better about throwing away food? Is this really recycling, or is it a waste of resources at one step removed?

60% of the world's crop yield is the direct result of fossil fuel derived fertilizers. Recycling food is recycling fossil fuels, otherwise it just ends up rotting into the environment and polluting it just the same as burning the fuels except you aren't doing anything with it if it just rots in a landfill.

> Recycling food is recycling fossil fuels

How much fuel do you have to burn to turn that waste food into usable nitrates? If it requires less fuel than the Haber-Bosch process, then why is it not profitable?

Or you can compost it into fertilizer. It isn't profitable because fossil fuels are artificially cheap and aren't paying for the externalized costs of pollution. Also, if you did it right you can also burn food directly as fuel.

Haber-Bosch process isn't a free lunch where free energy just pops into existence.

> " It isn't profitable because fossil fuels are artificially cheap "

Not that cheap. In the aforementioned metal recycling example, the energy is typically coming from fossil fuels too; refining aluminum from ore takes an insane amount of electrical power. Even if you do that with renewable energy, that's still that much power that can't be used for other things that must be supplied by another power source (e.g. fossil fuels.)

That just indicates that metal recycling is super advantageous, to be profitable even with the abnormally low price of energy.

A lot of natural gas is stranded or considered a waste product of oil production.

So fertilizer plants in those areas suck up that cheap CH4 to reform it into H2 and heat up the Haber-Bosch process to make ammonia and then into more transportable fertilizers like urea.

You place aluminium plants where the energy is cheap e.g. Iceland, it is often cheap because it's hard to export energy.

> If it requires less fuel than the Haber-Bosch process, then why is it not profitable?

That was clearly intended as a zing, but it just shows you aren't thinking about this right. Conventional ammonia production is vastly less efficient than just composting your garbage. Be real here. Bacteria literally do the job at a labor cost of zero and all you need to do is keep it in a stable environment.

What hurts is what always hurts: scale. If the composting facility is across town, you also need to haul the biomass around and haul the fertilizer back. If the industry is tooled up to spread pellet fertilizer it's going to see an immediate cost moving to equipment that can spread and till compost.

But stop pretending that there's an "efficiency" argument to baking nitrogen into ammonia in a 20 barr, 500C pressure cooker. That's nonsense.

I felt like the parent was asking the question not as a zing but an earnest question.

I'm a deep green (I don't eat meat, I don't fly, I don't drive), but I'm also a skeptical green. There is an overwhelming presumption that recycling must be good for the environment, but the evidence is often weak or nonexistent. I'd be more than happy to support food waste recycling if someone can provide good evidence that it actually is environmentally beneficial.

The classic example is plastic versus re-usable glass bottles - plastic nearly always proves to be more sustainable than glass, because glass bottles require vastly more energy to manufacture, they're much heavier to transport, they require surprisingly large amounts of energy to wash and they have relatively short average lifespans. The plastic waste issue is quite effectively solved by just burning it - plastic waste is a perfectly good hydrocarbon fuel.


"I'd be more than happy to support food waste recycling if someone can provide good evidence that it actually is environmentally beneficial."

I'd suggest checking out a resource like "City to Soil": https://www.gerrygillespie.net/city-to-soil.html or "Ecologically sustainable recovery of bio-waste" https://www.umweltbundesamt.de/sites/default/files/medien/37... or anything at "Zero Waste Europe" https://zerowasteeurope.eu/.

The key points: Food is the basis of the human economy. Collecting and composting food waste closes the loop and completes the nutrient cycle in the soil we use to grow food.

Not to mention: half the problems we have with traditional dirty landfills is that the unsorted food waste starts to decompose (releasing methane) and creates a hot environment that causes everything else to degrade in a toxic manner. As soon as you take it out, you have a "dry" landfill, where currently unrecyclable single-use things can be stored in GPS-tagged storage sites, until someone finds a better use for them and/or we start to phase them out.

The only relevant data I could find in those links was from "ecologically sustainable recovery of bio-waste". A figure on page 38 suggests that bio-waste recovery could save between 29 and 194kg CO2e per ton of waste, but the breakdown does not appear to include the emissions involved in the collection of domestic food waste and the accompanying text acknowledges that the data is not based on a full lifecycle analysis. I cannot find the source document cited in the figure, possibly because of a translation issue from the original German.

>The plastic waste issue is quite effectively solved by just burning it - plastic waste is a perfectly good hydrocarbon fuel.

How about the pollution caused by burning plastic waste? Take dioxins, for just one example. I've read that they are released when you burn plastic (don't have a link handy).


"someone can provide good evidence that it actually is environmentally beneficial"

I don't think anyone is, just that its less bad than the alternatives.

You don't drive, presumably you walk or cycle then. Each of those activities have negative environmental externalities compared to not doing them, after all you have to consume extra calories. So while each is infinitely better than driving, they aren't environmentally beneficial.

With your plastic v glass example, you seem to be using sustainability in a way that I wouldn't recognise, to me sustainability is about how long you can keep doing something regardless of how much energy it requires (up to a point, and assuming clean energy sources). The glass is infinitely recyclable, the plastic isn't. Especially when burned, so I would say the glass is sustainable.

"to me sustainability is about how long you can keep doing something [...] glass is infinitely recyclable, the plastic isn't"

Exactly - it's about reuse (ie. infinitely recyclable), and the shift in thinking that comes along with that.

Burning plastic releases toxic byproducts into the local environment, and requires us to use more fossil fuel hydrocarbons to make new plastic.

On the other hand, instead of transporting glass bottles across half the country, why not refill them in a local bottling plant, using local produce? Glass bottles can be washed 50-100 times, and after that they can simply be remade into new glass.

In Germany today, there are 5 standard glass beer bottles that everyone uses, so they can be refilled by local breweries all around the country. If a country is thinking of implementing a similar system, it would also be wise to invest in container deposit scheme, to ensure the bottles get returned in a good condition for reuse. Return rates in Germany are upwards of 98%.

It wasn't long ago, when our parents/grandparents/great-grandparents were getting milk delivered in glass bottles, to be washed, refilled and reused. We could easily go back to those more sustainable plastic-free times.

The key mistake of GP and yours here is this part of GP quote you elided:

> regardless of how much energy it requires (up to a point, and assuming clean energy sources)

The world isn't yet powered through clean energy sources in any significant way. Electricity production runs mostly on fossil fuels, and then electricity is currently only a part of the equation - heating and transportation is still mostly powered by burning hydrocarbons pulled from the ground.

It is not just valid, but very important, to consider sustainability in context of system at the whole. Greedy algorithms don't work here. A glass bottle may be "infinitely recyclable", but if doing the actual recycling involves using energy from unsustainable sources, it's not a sustainable behaviour in itself. Sustainability is an end-to-end thing; if any link isn't, the whole chain isn't.

Now that we've established that glass recycling isn't currently a sustainable practice, we can still consider whether it's better or worse than alternative unsustainable practices. Regular "single use, thin plastic bottles, destination: landfill" approach seems idiotic. But alternatives involve "thick, refillable plastic bottles" (something I recall Germany used to do), or "single use, thin plastic bottles, destination: power plant" which isn't as dumb as it sounds - if it could be made the primary fuel source for said power plants, it's a step up. I reserve judgment on the alternatives, as I have no data. And it's kind of a problem today: regular people don't have an easy way to review end-to-end performance of such strategies. So they vote for convenience, or for whatever looks ecologic.

Burning hydrocarbons has still place in a sustainable future - they're a great high-density energy store, after all. But to make the chain end-to-end sustainable, we'd have to be using clean and sustainable sources to take back all the emissions and to manufacture more hydrocarbons.

EDIT: And to be clear, I'm always biased in favour of reusing and (then) recycling. But the energy calculation has to make sense, because sustainability is in big part an energy management problem (the other big part is habitability management problem - not doing net damage to the ecosystem; but, assuming the will to do it, it also quickly becomes a subset of energy management).

Right, I'm talking about technically feasible solutions. And it is entirely feasible to power the world with clean, renewable energy. We have the solar capacity to meet hundreds of times our current energy capacity (using less land space than our existing roads). And over 530,000 potential pumped-hydro sites worldwide to store that energy (of which we'd only need a tiny fraction). For example, there are 22,000 sites in Australia, of which we'd only need 20. The research shows that cost will be a non-issue.


Everything else comes down to barriers in the economic and political domains.

But we don't currently live in a world that's powered by renewable energy, we live in a world where the vast majority of energy is generated from fossil sources. Making that transition will require decades, billions in investment and a lot of challenging trade-offs.

Here in the real world of 2019, energy is the dominant factor. If we need to dig up landfills to recover materials in 2100, so be it - right now, we have a ticking clock to mitigate the worst effects of the impending climate crisis. We simply cannot afford to waste time on wishful thinking and idealism, we need to cut our carbon emissions hard and fast.

"If we need to dig up landfills to recover materials in 2100, so be it"

You were talking about burning plastic bottles a minute ago???

Agreed we need to minimise energy usage and move away from fossil fuels as quickly as possible, plastic usage risks creating a market for fossil fuels, where petrol/gas become cheap byproducts, so it isn't a straight forward trade off.


The way I see it, we need to optimize our energy use and ecosystem damage output, until we can switch over completely to surplus clean energy. After that, a lot of ecology talk stops to matter. For instance, with surplus energy put to use in collecting, recycling & emission capture, we could use disposable plastics to our hearts' content.

Unfortunately, as you say, widespread deployment of clean & sustainable energy sources comes down to barriers in the economic and political domains. That's why I feel modern ecology needs to optimize for reducing energy use, even if it might mean preferring some locally suboptimal-looking solutions that turn out to be globally more efficient.

"The key mistake"

Not really because I wrote it.

I could have written 'glass recycling has the possibility to be sustainable', but instead I wrote 'glass recycling is sustainable assuming X'

You could complain if I didn't state my assumptions, but I did.

I currently buy 100% green electricity, I could use that to recycle glass today and that would be sustainable. So this isn't some hypothetical, it is possible today.

That isn't to say that I disagree with your points though. It isn't an easy problem, and 'best' now, doesn't necessarily match 'best' in an ideal world.

What percentage of fossil fuel consumption is that? How does food per capita compare to transportation (caets) per capita, in terms of fossil fuel use?

Does converting fossil fuels into food fertilizer cause pollution? Transfering waste from an oilfield to a landfill isn't inherently unecological.

It certainly can be a reduction if you can compost at home. The result is useful. The effort is very minimal if you don't need it to compost quickly. It doesn't need to be transported to a landfill. And my understanding is that it breaks down into carbon dioxide instead of methane if you compost instead of landfill, which is a win for climate change.

I live in a rural area without refuse collection. Having to deal with it all yourself really focuses the mind on keeping waste of all types to a minumum. I suspect more fees for waste collection is what would do likewise for urban dwellers.

We live in a rural area as well and we have to take any trash either to the dump or a convenience center. Since we compost, recycle, and raise a significant percentage of our food, we only actually need to take trash to the dump once a month at most.

I compost and one selfish advantage is I now never run out of space in my bin. That food waste takes up a lot of volume.

One can extract the energy in food?

Primarily digestion, but for "left-overs" or food waste and scraps there's vermiculture and composting. I guess we have mass digesters now too to turn the material into heat.

I mean, that's exactly how kcal count is measured - a portion of food is burnt and the energy released is then measured.

You can't measure nutritional values like that. Not everything that can be burned is available to the human metabolism. Cellulose being one obvious example.

That's true, but we aren't usually burning things that humans would not normally eat. There's a lot of variations on measuring calories (not nutritional value, two different things), but the method of the Calorimeter is pretty standard and in line with the parent's comment.


Isn't that how all food is measured though?

no, foods are analyzed for their digestible contents (fats, fiber, carbs, various kinds of alcohos etc.) and their energy content is then looked up in reference tables. The reference tables are in turn populated with more careful experiments that take digestion, waste products and metabolic efficiency into account.

Directly measuring the physiological energy content for millions of food products would be impractical.

It is burned to measure total energy and then a model is applied to approximate the calories available to the body.

That's how it was measured, once. Now it is measured based on the components of the food (fat, carbohydrates, and protein).

> There’s a limit to how much food waste fertilizer can actually be used

once upon a time we fed food waste to animals to "recycle" the caloric content. Think table scraps(but not meat) going to pigs or chickens.

Would be interesting if we close the loop on this household content

Edit: Added note that I meant "vegan" scraps.

Yes my uncle used to feed almost all food waste to his pigs. Then we ate the pigs. Unfortunately suburban Silicon Valley residents don't appreciate backyard pigs.

Chicken will eat a lot of table scraps and are backyard friendly in many places

Chickens will eat almost anything you throw at them.

Stopped in the UK due to BSE, and not being able to audit ingredients.

I wonder if cockcroach protein powder would bypass brain wasting disease and other nasties.

Black flies and worms are currently tested in The Netherlands. It’s 10 times more expensive vs other protein sources, mostly byproducts from human food production.

Dutch source: http://edepot.wur.nl/362233

I believe in China it was common to site toilets over pig stys. Some loop closing isn't a very good idea.


About 20 years ago I stayed for two weeks on a rural rice farm in Goa.

The toilets fed directly into the pig sty. Very directly down a short chute add though a hole. An eager pig snout poked through the hole could make contact. Never before nor never again have I been so startled.

But... why...

Pigs don’t eat human faeces...

Pigs eat anything. Well, maybe not rocks. I'm not sure about that though, they might still try.

If you want to see what happens when pigs that eat near human faeces are eaten by us: https://www.cnn.com/2019/03/28/health/brain-parasites-case-s...

The CDC specifically say that you don’t get cysticerosis from eating pork, though the correlation with pigs eating human faeces is mentioned. As always, it seems that washing your hands is important.


I have seen first hand that they do, not that I wish I hadn't.

Pigs eat everything, including humans.

Pigs even eat pork. There is currently a problem with swine fever infected pork being reintroduced as feed in places like china. It is one of several vectors for the lethal (to pigs) disease.

Well to be fair, if you were served some nameless meat, would you be confident in your ability to identify human and/ or not like the taste of it?

Chickens will eat egg shells, and it's apparently a good source of minerals for them. You do have to scrunch them up, or else, from what I understand, they start associating egg shells with food, and start pecking their own eggs.

Its also good to bake them for a bit. It helps with the 'scrunching' and nutrient availability (so I've been told).


Much of the 'compost' you receive at big-box stores is treated human waste: https://www.epa.gov/biosolids/frequent-questions-about-bioso...

Not much goes to waste in the USA on an industrial scale.

> Much of the 'compost' you receive at big-box stores is treated human waste: https://www.epa.gov/biosolids/frequent-questions-about-bioso...

I don't see anything on that page to support this specific claim.

> So Milorganite is actually a bag of dried microbes!

great marketing

The page says "Biosolids are treated sewage sludge."

Sewage sludge is feces

Is feeding meat to chickens and pigs a bad idea? I get that brain matter could cause prion diseases in cows.

Every time I ate pork there they always bragged about how it had been fed garbage T_T When I researched it later, it turned out that in the US we stopped feeding leftovers to pigs a long time ago due to health concerns. Laws were passed stipulating that garbage be boiled before being fed to pigs, but that made it too expensive so everyone stopped doing it.

Here in the SF Bay Area, some cities have started collecting food waste to be treated and fed to animals. There's been some minor backlash, due to the uncertainties around what goes into the food waste bin and how that gets treated and sorted and eventually processed into animal feed. I'm not aware of the law you mentioned, but it's being done.

It's important to bring up the Food Recovery Hierarchy when talking about food waste. Composting is not the least desirable outcome, but it is close. We really need to focus on the higher priority reduction methods:


This implies composting food waste is only slightly better than landfill, which is obviously absurd.

Illustrating that the next best existing option after composting is landfill, says nothing of the delta separating the two on the efficacy axis. It only speaks to a lack of altnernatives separating composting and landfill.

I'd argue that burying your food waste in any land that food will potentially be grown in is infinitely superior to sticking it in a landfill where food will never be deliberately grown.

From my perspective, living on a rural property with an outhouse where all food waste and human waste is buried and eventually grown food from your comment strikes me as ridiculous. I add obvious value to my land burying this waste, it completely escapes reuse, effectively exiting the system, when I put it in the dumpster.

There is a high loss to atmosphere/runoff on burying your food in the soil for recovering it later as available fertilizer nutrients.

There is 100% loss of what's sent to the landfill, while consuming energy to move it there.

On my property in particular, runoff is not an issue (desert). From what I've seen there's mostly increased insect activity in the compost area. I view it as more generally increasing the fertility of the area from waste using minimal effort.

Most of it is consumed by other lifeforms before I grow anything there. But those lifeforms are residents of my land and will continue to multiply (and die) here. Their increased activity effectively locks up the resources and I can leverage that with a large garden when time permits.

The landfill has CH4 off gassing, which is usually burned and used to power things. It also supports it's own ecology and residents. The transporting of rotting food around is pretty ridiculous though.

You might make your distributed practices even more efficient with vermicompost / bokashi; by selecting an organism with known beneficial outputs to metabolize the waste you'll end up with a higher conversion to usable nutrients and beneficial microbes for your plants.

"which is usually burned"

Have you got any sources for the usually?

Any ex landfill I've seen just has vents to the open air, and mentions of landfill gas never give the impression its mainstream.

There are plenty of landfill gas capture systems around. Veolia are particularly proud of their so-called "Bio-reactor". These kinds of systems don't work as well as advertised, but if you have a landfill, it's better than nothing. https://www.veolia.com/anz/our-services/our-facilities/landf...

But as others have been saying, it makes much more sense to simply bury the food in your garden. Or collect food waste on a municipal level, which has, for example, been the law in Germany since 2015.

The "dry fermentation" system used in Munich is a particularly good example. They collect food waste in the city, compost and ferment it in a big sealed hall near the soccer stadium, wait 12 weeks for the bacteria to work, collect the resulting biogas to put into their gas network (or power garbage trucks), and sell the leftover organic compost and fertilisers to local residents and farmers. A closed and sustainable cycle.



This seems like a ridiculous chart. First of all, no homeless people or animals want to eat leaf litter, moldy vegetables, or coffee grounds. Second of all, the only inputs to my garden are water, sunlight, and compost, so as far as I'm concerned composting garden scraps is net zero at worst.

There is a lot of waste in the food supply chain. Some of that is suitable for human consumption at the point where it is classified as waste [1]. In Europe the food waste in fruit and vegetables is over 50% [2], of which at least half could be turned into black soldier fly or mealworm feed, which makes for good poultry or fish feed. But most of it today is going into waste dumps or at best turned into biogas.

Disclosure, I work for a startup that turns this into a circular food production system, from food waste, via insects to fish and vegetables via aquaponics.

[1] EU rules say eggs should be marked “Best before date” as 28 days after they have been laid, but stored propperly they are good for at least double that time. (Swedish) http://www.svenskaagg.se/?p=19895 In the UK supposedly 720 million eggs are thrown away each year. https://www.independent.co.uk/life-style/food-and-drink/eggs...

[2] http://www.fao.org/3/mb060e/mb060e00.htm

Can you share which startup you work for? I've been wanting to work for a company like that

From bjelkeman-again's HN profile: "CO-founder & co-director at http://akvo.org ... We build open source data systems which we run as a service that are used in international development and increasingly in country governance."

From https://akvo.org/ "With our unique approach to development, we help our partners design their projects so that they can capture and understand reliable data which they can act upon."

Thanks, updated my profile to include our new startup.

This is a new one, Johanna’s Urban Farms, in Stockholm. We are just now building the pilot installation. https://www.johannas.org


Before Haber–Bosch, everyone recycled 100% of their food waste.

And countries went batshit crazy - Saltpetre war with Chile vs Bolivia and Peru were fought over caves with bat guano which was the most valuable fertiliser of the day.

"per capita food waste in Europe and North America is 95kg to 105kg a year"

That's a massive amount, and that is just waste in the household, not waste in the farm or factory.

I can understand some wastage of salad and berries etc, but they're all lighter stuff. How can the average westerner waste 2kg food a week???

Yes that sounds insane. That's 0.6 lbs food per day, which is the same as throwing away by weight every day (using McD's as an internationally recognizable reference):

- 1.5 McDonald's quarter-pounder sandwiches [1]

- or 2.5 portions of McDonald's medium fries [2]

That seems like a lot of food to waste. Like that just doesn't pass the smell test...

Maybe they're counting liquids like milk too, that's gone past the expiration date? Otherwise I just can't wrap my head around this.

[1] https://en.wikipedia.org/wiki/Quarter_Pounder#Product_descri...

[2] https://www.mcdonalds.com/gb/en-gb/help/faq/19041-how-much-d...

Of course it should count as food waste if you let your milk expire and throw/pour it away (or worse, pour it away because it's past the expiration date, even though it's still perfectly fine)

"mass" is a poor measure of food waste because many foods are primarily water.

That sounds low, based on the American families I know...

I always want to know where that's measured. Presumably it includes food that went bad in the fridge, and food that was thrown away from the plate. But does it also include apple cores, animal bones, coffee grounds, onion peels, citrus rinds, banana peels, and so on & so forth? In a perfect world we'd make more soup stock, zest, and marmalade but I think compost is a pretty reasonable path for carrot tops and potato eyes.

Or foods that don’t require peeling, like potatoes, carrots or cucumbers.

On that note, it’s nearing time for me to make more limoncello/orangecello...

Between throwing out food that's gone bad and leaving unfinished plates at restaurants, I can absolutely believe that. There are some who strictly abide by the packaging expiration date and many people don't package the remainder of their restaurant dish to take home.

It took me a long time when I first started living alone and taking care of all my meals to figure out how to not waste my food, mostly through trial, error, and taking note of every single useful bit of advice I came across online or in meatspace.

I still don’t think I’m particularly efficient, just that I waste a lot less than I used to, and if I could fit a freezer chest in my apartment, I know a few ways that I could waste even less. Mainly what I do now is to shop at a local grocery just about every day, I’m blessed with an abundance of those and good options, and try not to buy more than I will cook in a day or two. This has become easier since switching to an almost entirely meat, egg and vegetable diet so I don’t have dairy products, soy products, bread, pasta, cereals, noodles, beans, or anything besides my spices, dried herbs, salts, oils and vinegars sitting around. Despite that, I still end up throwing away more than I would like every few weeks, but probably not 2kg a week.

Had I grown up in a household with people that knew how to manage a household, it would have been a lot less trial and error, but with our over reliance on packaged foods instead of just what you can find in the produce section and at the butcher, probably a lot of people like me are growing up not learning how to manage their pantries and fridges.

That’s without even factoring in restaurants. It isn’t uncommon for people to not finish their food and leave it rather than taking the rest with them, and more so the more people eat out. Rather than finishing their leftovers at home, if they even took it home, people will often just go out to eat again the next day.

I've lived with a variety of random people in shared circumstances, and it seems quite common for people to pack a refrigerator with perishables either in the form of leftovers or new groceries then forget it exists while continuing to eat the most convenient stuff at restaurants/the office.

Refrigeration in general encourages the behavior, without delivering on convenience since you generally have to reheat or partially recook the food only to have something inferior to the more convenient, freshly made by someone else option.

People I've known feel accomplished just by asking to take leftovers home and placing them in the refrigerator with the feigned intention of eating them, knowing full well they will spoil and go to waste. It's an absurdity; they add packaging waste (often plastic at least in the bag) to their charade, mostly because they don't want to appear wasteful at the location they didn't finish their meal, and wish to dispose of it in the privacy of their home after spending energy on refrigerating it for a week.

I can't understand "feeling accomplished" by getting a doggy bag.

In the more superficial of my peers, just maintaining an appearance of someone that isn't wasteful is an accomplishment. They live incredibly wasteful lives, but especially on the west coast, it's very hip to appear like you care about the environment and aren't being wasteful.

Then if you throw some sociopathy into the mix, there's an even greater sense of accomplishment in knowing what you're doing is actually increasing the waste by pointlessly packaging up the food destined for the landfill because you'll never actually eat it. Inconveniencing the staff to package your leftovers on top of it is just gravy.

It’s very easy. At least in the US, portion sizes are too big. If you go to a restaurant it’s profitable for them to increase the size of a meal by 50% and charge 25% more, which looks like a cost savings and value. But then the food ends up being wasted.

Many people don't eat leftovers. In some cases it's cheaper to buy 5 lbs of something and throw out 2 pounds than to pay for 3 1-lb packages.

Have you ever been to a restaurant? Most people throw out over 25% of the food on their plates.

This is all a symptom of a distorted market place. Food's too cheap thanks to subsidized farming.

"Have you ever been to a restaurant? Most people throw out over 25% of the food on their plates"

I've worked in a few. As a European I'd say food waste was lower than that.

Id expect restaurant food waste to be higher, as they can't personalise portion sizes as effectively, so unless most people eat out most days, I don't see how that could account for all the waste.

But apparently it does? I really hope peelings etc are included, because even then there's still a family out there wasting 3kg+ of food/person/wk, just to balance my family out.

Europeans out out a lot less than most places in the world. Perhaps a stronger home-cooking culture.


Looks like it's about twice as often as in Europe. Interestingly Asia/Pacific is even higher (cheap street food FTW!)

I don't think we have to look further than the convenience culture to explain the behavior. It's not, in my experience, economical at all. The people I see wasting food are being very wasteful of their money in the process, they're just being stupid and careless.

Well, I'd argue, it's because they can afford to. Most people don't throw away relatively more expensive items. If a pound of meat cost $30, would people be so careless with it?

Merely growing up poor fixes that problem. Older family members would finish off a lot more from each chicken wing than I would.

> Have you ever been to a restaurant? Most people throw out over 25% of the food on their plates.

It is easy to order a smaller portion of most meals. The problem lies on the client in this case.

Is it? Most non-fast food places get cranky if you try to order off the kids menu.

I mean half a portion of regular selection, not the kids menu. They would happily prepare even if you would pay the same price in the worst case.

This probably includes all stages of the food value chain. A good chunk will be at the farmer but in general their scale is big enough that they can redirect to animal feed. Or a it could be at the grocer who bought too much carrots and they are starting to wilt. But at this stage things are mixed up too much so more likely to be redirected for compost. Or it could be at the restaurant which gives you a big plate of food but you are full and don't take the rest home.


I don’t think it’s in the purely personal sense. Imagine how much unused food must be thrown out at restaurants and delicatessens. Buffet and prepared foods probably don’t roll over into the next day.

Food has a high % of water content and is therefore very heavy.

If anything, Americans should be throwing out even more food. With the astronomical obesity rates, I don't think we should be encouraging people to finish what's on their plate.

If that seems wasteful to you, then I assert you're not looking at the big picture. Habitual overeating causes even worse portion control in the future, which causes even more food waste in the long run.

The cure for obesity is making better choices at the store, not at home.

Poor portion control plays a large role in it. A great many people simply eat way too much.

Portion control means making and serving smaller portions. Not throwing out half the food on your plate.

Portion control means serving yourself less, but failing that, it means stopping when you're full, not continuing to eat what you've served yourself in the name of preventing food waste. Once you start doing that, you reinforce the behavior of serving yourself too much and eventually begin to crave more food than you should be eating. Portion control is unrelated to how much food you make, assuming you have a refrigerator and don't think yourself too good for leftovers...

> not continuing to eat what you've served yourself in the name of preventing food waste

You could also cover your plate and put it in the fridge. Doing that requires the same amount of self-control as your prescription of clearing your plate in the trash once you're full. Both are hard for many people to do.

It's easier to exercise restraint when serving than when eating. For example, Google successfully reduced food consumption and food waste by reducing the plate size in cafes. [1]

> Portion control is unrelated to how much food you make

Not entirely. Even in the fridge, food will only stay good for a certain amount of time. Most people won't want to eat the same thing more than 3 meals in a row. These are also reasons for overeating or throwing food out.

1. https://www.linkedin.com/pulse/how-i-lost-30-pounds-over-two...

I note that most replies seem to point to the bad habits of others.

This is an average. Everyone is wasting this on average. So presumably there's either a stigma against wasting food, which makes it all the more crazy, and/or people that waste food aren't interested in this kind of article. That would suggest they waste even more than average.

Keep in mind that a lot of that "waste" happens before the food reaches us consumers.

This is just the consumer waste. Ie the red bit of that first chart.

I'll admit I didn't read the article :/

Do you eat onion peels? How about banana peel? Do you eat the bones of meat? 2kg isn’t that much.

My neighbors probably hate me but I compost all my food in the backyard. Last year was the first year we did it overwinter when the compost isn't even active and it also was the first year we didn't have mice in the house.

I know you're probably joking, but for the sake of anybody reading this who may be consider composting: A healthy compost doesn't smell bad (I honestly kind of like the smell) and doesn't smell strongly either, so neighbors won't mind or even know it's there. I compost in my small patio; there's table and chairs just a couple feet from the composter and it hasn't been a problem.

Good compost does not smell but does attract (in NA) the likes of racoons and black bears and some people vocally don't like that.

It also attracts lots of insects. While it's ok in general, you probably don't want a farm of them right next to where you sit/eat.

In Taiwan, that translates to giant flying cockroaches. And the giant wolf spiders that eat them.

And as I discovered last week, bees hate fresh compost. Don’t dig it in the near a beehive.

Food used on farms decomposes directly into the atmosphere, including methane. Food sent to landfill decomposes poorly with an increased methane output, but some of the methane can be captured to generate electricity.

I'm not qualified at all to analyze this properly. The former method makes use of food to displace use of fossil fuels in farming. The latter displaces use of fossil fuels for electricity generation.

Is there research which demonstrates that one method is better than the other?

I recently learnt of a food waste recycling method that avoids decomposition and release of methane. It is called bokashi and it uses homolactic fermentation to break down the food waste. Quoting the wikipedia article [1]:

> Homolactic fermentation breaks no carbon bonds and emits no gas; its overall equation is C6H12O6 (carbohydrate) → 2 CH3CHOHCOOH (lactic acid). It is a mildly endothermic reaction, emitting no energy; the fermentation vessel remains at ambient temperature.

Interestingly, this method was historically developed in Korea, as is also detailed in the wikipedia article.

[1] https://en.wikipedia.org/wiki/Bokashi_(horticulture)

"It is a mildly endothermic reaction, emitting no energy; the fermentation vessel remains at ambient temperature"

Surely if its endothermic the container would get cool???

Perhaps that part of the article could be edited to "remains close to ambient temperature".

That's awesome!

Food waste seems so very easily preventable. Take what you want, but eat what you take. Composting what's left over is an awesome idea.

Food waste is a bigger issue than people putting too much on their plates. One of the highest sources of food waste is in the "manufacturing"/distribution phases -- malformed, misshapen, and otherwise "unsalable" produce is either left unpicked in the fields or rejected by groceries. More waste comes from rejections due to food safety regulations, overproduction, logistical errors resulting in spoilage, and the simple fact of groceries needing to display full bins/shelves of food at all times, even for low-volume products which they can never hope to sell in time.

It's like when individuals are made to feel bad over taking a five minute shower instead of a three minute shower, while Nestle is extracting millions of gallons of water without paying a cent for it. Individuals should absolutely do everything they can to reduce their own food waste, and composting is better than nothing, but as a global society we should really be focusing our efforts on the largest sources of waste first.

Let us assume that 90% of food is wasted before consumers even see it. Any reduction in demand has an outsize waste reduction because every kg results in another 9kg not being produced and wasted further up the chain.

So yes that 90% headline should definitely be cut, it is our waste, and we should be doing everything we can our end also.

More than 50% of food (quantitive) drops in the supply chain, before arrival on any plate.

Is it no longer waste if it sits on your gut?

No, then it's waist;D

that's just insane. I start to see more and more news about countries that understand how crucial it is to recycle.

But do they feed it back to the fabricants already ?

They can make a lot of Kimchi with all that fermentation.

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