Sarah Bridle: Food and Climate Change

please give a very warm welcome to sarah bridal that's great thank you thank you thank you very much indeed well thank you for coming and uh coming to hear about this really interesting topic and so i'm going to be talking about a bit about climate change i gave this a similar talk last year and the year before at blue dot and while i was preparing my slides for this talk i realized that i needed to cut lots of my slides on climate change because there's been so much talk about it in the last year but just a quick question oh that's the wrong wrong button hold on let's try that again there we go right button okay so big question hands up if you think this graph of temperature against number of years is this graph going up hands up if you think it's going up okay thank you our hands up if you think it's not going up okay i just root out the the controversies early on okay that's great so this is the graph that my colleague brian cox threw at the the climate skeptic in australia um and the discussion there was about whether this graph is going up uh the scientific consensus from the international committee on climate change uh warming of the climate system is unequivocal there's another version of this which i think is really beautiful why is this not working okay here we go this is a beautiful project uh called climate stripes you can download this for your own city or country and this is just showing the average temperature for each year since 1850 and it's showing it in different colors so the question here would be do you think that one side of the graph is more red than the other side of the graph um i can see some laughing there okay but no matter what uh you think about what's happened in the past okay this is not working as well as i'd expected i shall just press the button okay so no matter what's happened in the past really we're all concerned about what's going to happen in the future and so this kind of graph of the amount of carbon dioxide in the atmosphere going up here now now above 400 parts per million is really what's important if you believe the science about global warming saying that light's going to come in from out at the the sun it's going to warm up the earth and then that infrared radiation that heat is trapped by these greenhouse gases so if we look into the future well we don't know nobody knows what's going to happen in the future but these are some different scenarios that have been considered by the international scientific community uh depending on how much greenhouse gas emissions uh going up there as a function of time or maybe we will reduce greenhouse gas emissions and eventually be sucking carbon dioxide out of the atmosphere by the end of the century this mouse button is going a bit crazy let's put this down okay so no matter which of those we're on it turns out that the more greenhouse gas emissions we have on the bottom of this graph then the higher the temperature at the end of the century very roughly so for the rest of this talk we're going to be focusing on the amount of greenhouse gas emissions i'm going to try an audience poll so i'm going to try an audience poll of how much more food do you think we're going to need by 2050 so i've got a few options for you here so i'm going to ask for hands up if you think we're going to need 10 more food by 2050 thank you hands up for 20 more food by 2050 okay hands up with 30 more food hands up for 50 more food hands up for 70 more food great so different estimates say different things i think this room has said between 30 and 50 percent uh most estimates say 50 or more percent more food so this is the world resources institute version of that calculation uh different versions depending on the projection for the population of the world which obviously is a very important factor and then the other important factor is how much each person uh how much food each person wants and so you can see here a graph showing the amount of calories people want versus the amount of money that they have roughly and so what you can see here is that the more more money people have the more calories people want there's a really interesting uh thing you can see already on this anybody anybody been on a diet ever okay no one's owning it to it this evening but if you've ever been on a diet then you will know roughly the amount of calories that people need is about 2 000 to 2 500 calories so what's happening why why are there so many people wanting more than 3 000 calories two main reasons obesity and food waste so there is lots of people wanting more food than they really need which is one big issue so that that partly drives that number that we just saw so are we going to try and meet the global demand for food or do we need to manage our demand for food okay if we look into the future then we've got an impact of climate change on food production so if we look ahead then more carbon dioxide in the atmosphere can have some benefits so for example global warming can cause some countries which had maybe the cooler climates can actually produce more food so some people benefit from global warming but at the same time we can also some plants actually grow faster when there is more carbon dioxide but the disadvantages are that often the nutrition is lower in the plants which grow faster and that's a serious issue that's being considered a lot in the scientific community at the moment but another problem of course there are many countries especially near the equator which produce a lot less food so on average globally we're going to see a lot of yields going down producing the lower of these two bits of millet here rather than the upper for example depending on the weather and then depending on how you do the calculation a reduction in yield and a corresponding increase in the price of food now factually when you have an increase in the price of food then that can cause other problems beyond the food system this is a very now famous graph showing the price of food and in red food related civil unrest uh which you know we we don't know what's going to happen in the future sometimes it's a perceived lack of food rather than an actual lack of food but this is these are issues we need to consider maybe other new foods that we hadn't previously eaten so much of will become more popular anybody anybody like black eye beans here hands up there's lots of people here wow fantastic so this is a type of food that's been investigated as a potential food that could grow in space because it's so hardy but i i thought i would google some delicious recipes using black eyed beans so you can check those out later if you didn't put your hand up already and so there's lots of possible outcomes most of this talk i'm going to be talking about a different topic the impact of food production on climate change so i'm going to do another poll now what fraction do you think what fraction of greenhouse gas emissions globally come from food production including agriculture land clearance for agriculture food processing transportation and so on so i'm going to do a poll so who thinks five percent of greenhouse gas emissions come from food okay who thinks 10 hands up who thinks 20 thank you who thinks 30 percent who thinks fifty percent and who thinks i'm trying to trick you by giving you another question which was right off the chart so yeah it depending on how you do the exact numbers it's currently between about 20 and 30 percent of greenhouse gas emissions coming from food but if we look into the future then as there are more people demanding more food this number is expected to go up if people are demanding more carbon intensive or more greenhouse gas emitting foods this number will also go up but also as we have more renewable energy in the rest rest of the the greenhouse gas emissions might go down hopefully and food will become an increasingly large fraction of the greenhouse gas emissions so i think this is going to be where we're talking about in 10 20 30 years time about greenhouse gas emissions it's going to be about food i won't go through this graph but the slides are on my on on our web page if you're interested to study it in more detail this shows you different types of activity and how they contribute to greenhouse gas emissions there's a beautiful chart showing food here uh producing more greenhouse gas emissions for example than heating for personal comfort so warmth in houses and buildings more than mobility and freight there so this is a significant fraction of um of greenhouse gas emissions uh for those of you interested in more detail you can read this in your spare time but you can see a lot of detail on there which i think is just so fascinating and you can see you can see rice paddies on there cows you can see clearing of land for agriculture it's all on there so i got curious about this and i started to do some calculations uh every uh every year or two there is a survey of people in the uk asking them what they eat um and so this is done for about four days imagine writing down everything you eat for four days guess what on day four people eat less than on day one it's quite boring but this does happen and the data is analyzed and we analyze some of this data matching it up with the greenhouse gas emissions for different types of food and so what you can see on this graph here is the different amounts of energy from different types of food so we get the largest part of our energy from bread pasta cereals no great surprise there we can actually reverse this graph and change the order so that we're looking at the greenhouse gas emissions in order so what we can see here is the largest category on this graph here is greenhouse gas emissions from beef and lamb followed by milk and cream and then cheese and butter so this is this is already making up more than one third of the greenhouse gas missions and we're going to talk a bit more detail about that now i want to know why why do these particular foods cause greenhouse gas emissions so i do i do eat meat i do think this looks delicious i'm quite hungry right now not everybody in this room will agree with me but let's talk about cows and so this cow so innocent uh eating some grass there um it looks looks delightful uh countryside of the uk what could possibly be wrong uh i've we've been running a stand in the emission control uh exhibition space the last three days i've talked to lots of people lots of people are quite familiar with this so i think that's really a big change from last year this is a cow's stomach the cow's stomach has multiple compartments and the rumen compartment of the stomach contains microbes that turn about five percent of the calories eaten by a cow into methane which is burped i just like to correct a few people on this burped out of their mouths so um i don't know what cows burping look like but i i'm guessing this might be uh one so cows eat about 40 000 calories a day and so about five percent of that is causing uh methane to go into the atmosphere methane is about 30 times more powerful as a greenhouse gas than carbon dioxide so this is this is a serious issue but how can we calculate the greenhouse gas emissions from a piece of beef we need to know how long the cow is alive for uh burping uh methane uh into the atmosphere so in order to produce some beef we need to grow a calf from birth to uh when it's fully grown ideally and also we have to have a cow a mother cow alive for one extra year to produce one extra calf so if we look at this system in more detail we can calculate the greenhouse gas emissions from a piece of beef a majority of that comes from the methane we've been running a stand just in there as i said this is a photograph of us on the stand earlier today can you see these balloons in the background and some white balloons at the back there it took a while to blow them up some of them popped overnight but there's about 40 or 50 balloons there and i've been asking people how much steak do you think you need to eat to cause the equivalent of that amount of carbon dioxide to go up into the atmosphere i've not prepared a hands-up quiz for this but i've had a lot of different answers uh the the size of a cow i've had uh that answer um i've also had one gram so if we've had the full range one person uh was spot on about 50 grams that's about half the size of a piece of beef half the size of a beef burger a size piece of steak you're responsible for putting that much equivalent amount of carbon dioxide up into the atmosphere so we are not lobbying for any particular outcome from this we're scientists we want people to know the facts and to use those facts to try to understand what is best to do with this but this is one of the facts you might be interested to know that you could have five times as much chicken so about 270 grams of chicken that's a really big chicken breast or maybe two smaller chicken breasts for the same amount of greenhouse gas emissions or five times as much again of beans for the same amount of greenhouse gas emissions now i am i am getting a few questions about the beans i think i should address this now uh there are concerns from a number of people who have visited our stand about personal emissions i'm going to call them so i need to tell you that the methane is not necessarily produced by people in response to beans it's actually genetic whether or not you happen to produce methane it's not linked to the beans however depending on the amino acid balance of the particular pulses or beans or lentils you're eating there can be more sulfurous emissions i'm just saying that and that's all i'm going to say on the topic so for example this is a very interesting study of new zealand lamb looking at the greenhouse gas emissions from lamb which have the same type of stomach as beef which i'm extremely disappointed about because i absolutely love lamb but in terms of greenhouse gas emissions then the majority of the greenhouse gas emissions are happening on the farm it's not the transportation by ship and so you know the details about the transport and the ocean shipping is not such a big big deal because of the methane being relatively large and the farm emissions being a relatively large part of the greenhouse gas emissions so that's one of the questions i often get asked about local versus the type of food that you choose i'm going to go back to this diagram now and talk about the next thing on the list which is milk and cream and cheese and butter so again i get asked a lot about packaging different types of milk bottle plastic versus glass and again the same story it's about what is in that packaging for the higher emissions foods it's much more about what you're buying than about the packaging for those higher emissions foods we're going to talk about cheese as well typically a cow might live for say four years uh producing milk for the second uh the second and sorry the last two of those years about half the beef in the uk comes from dairy herds so that's something that also shares some of the greenhouse gas emissions from the milk which helps to reduce the emissions from the beef and the milk if we can share those emissions out between different things we're back to the cows it's the same same animal producing the milk milk and the beef hands up if you've ever made cheese anyone made cheese here i can think i can see a few uh hands up there great so you know you put this uh rennet into the into the uh into the milk and you produce this uh this this gloopy stuff uh this uh this this lovely cheese now i've put this picture in here to illustrate the amount of whey that you produce when you uh make cheese so it turns out that to make one kilo of cheese you need about 10 kilos of milk so if so that increases the greenhouse gas emissions excuse me per kilo for cheese compared to milk it's about 10 times the greenhouse gas emissions for 100 grams of cheese than it is for 100 grams of milk so that's just that's that's basically why okay so i'm going to move on now to bread because that's that's one of the things that causes um the most uh it gives us the most energy but it's a relatively low emissions food so how do we make bread this is just a gratuitous picture of marmite on toast just to make me feel really even more hungry so i wish i hadn't put that in now but when we grow how do we make bread so we have to grow some wheat we have to take the grains out of the wheat and one of the things that we do when we grow wheat is we have to give it fertilizer so the main way that we get fertilizer for wheat is to use ammonium nitrate so this is nitrogen from the air combined under pressure in order to produce this synthetic fertilizer it looks a bit like sugar and about one teaspoon of ammonium nitrate is used to grow about enough wheat for two slices of bread but don't put this in your tea because it's also the main ingredient in lots of explosives so that's particularly interesting because whatever sort of fertilizer you use whether it's manure or whether it's synthetic fertilizer when you put fertilizer on the ground then microbes is microbes again microbes in the soil this time instead of microbes in the stomach of the cow these microbes in the soil will turn about one percent of the the nitrogen into nitrous oxide now nitrous oxide is also laughing gas um but it's no laughing matter because nitrous oxide is about 300 times more potent as a greenhouse gas than carbon dioxide so the main way that most plants plant-based foods contribute to greenhouse gas emissions is through the nitrous oxide that's put on the on the fields and also the production the energy that's used to produce the synthetic fertilizer about the same quantities of greenhouse gases from both of those those sources so we can do a calculation of how much greenhouse gas emissions come from bread uh you might be frightened by this number but it turns out that when you put it into perspective with all the other numbers then it's it's less of an issue we're going to make a cheese sandwich now we're going to make a cheese sandwich and we're going to calculate the greenhouse gas emissions from the different components of the cheese sandwich so we've got the bread two slices of bread uh we've got some butter we've got about that's about a tablespoon of butter and then we've got about 50 grams of cheese so this is roughly what happens when you add up the greenhouse gas emissions typical values for for greenhouse gas emissions so you can see there that the bread don't stress about the bread okay so this is you know what else could we do we could have what could we have instead of a cheese sandwich we could have a beef sandwich how about that so if we had a beef sandwich then that would cause more greenhouse gas emissions however what about a chicken sandwich so we could reduce the emissions by switching to a lower greenhouse gas emissions food like chicken where does the greenhouse gas emissions come from a chicken chickens don't burp as far as i'm aware i did actually read about i did type chickens burping into google just to check um apparently you can you can burp the little chicks to stop them from having bubbles i like you burp a baby so there is a there is some information on burping chickens but it's nothing to do with methane it's all about the food that is fed to the chickens so we have to grow food to feed animals like chickens and that is the main source of greenhouse gas emissions for something like a chicken so there's big differences between different sorts of food that's the main message i would have for you what other things we could do we could just reduce the amount of cheese so if we halve the amount of cheese maybe add a bit of pickle to make up for it then we can already make a big difference to the greenhouse gas emissions from the sandwich what about instead you can there's a lot of different cheese alternatives out there i'm not going to worry about that too much i'm going to suggest a bit of peanut butter and jam unless you're a nut allergy of course but peanut butter and jam is you know you can compare those numbers i'm not advocating any particular solution i'm just a scientist telling you the facts uh this is um the comparison of the numbers you could actually reduce your greenhouse gas emissions by nearly a factor of six by switching to a different alternative so there's a lot of information there a lot of things we can do to address you know reducing the amount of the highest emissions foods in our diet which would reduce the total emissions from a sandwich one thing i think we can probably all agree on um is that wasting food is is not a great thing to do i only learned a couple of years ago that it's not just because you've wasted the uh you know you've produced that food and when you produce the food it causes greenhouse gas emissions and you've just gone and thrown that away so what a waste of those greenhouse gas emissions that's not the main issue with food waste the main issue with food waste is that when food goes to landfill sites then it can't compost properly and it turns into methane so you've got carbon in the food it's trying to break down it's trying to rot when food is on a compost bin then it rots into carbon dioxide it has access to oxygen in the air and it carbon turns into carbon dioxide if you try to if you have food rotting where it does not have access to the air then it turns into methane which is carbon and four hydrogen atoms it doesn't have oxygen it can't produce carbon dioxide that sounds like it'd be better because oh carbon dioxide is a greenhouse gas right but actually methane for each carbon atom methane is 10 times more powerful as a greenhouse gas than carbon dioxide so basically what's happened if you grow food and then waste it and put it in landfill is that you've turned carbon dioxide into plants good we've taken carbon dioxide out of the atmosphere but then if it turns into methane then you've just just turned that carbon dioxide into something with 10 times the greenhouse gas effect but if it rots into carbon dioxide it's just returning that carbon dioxide into the atmosphere so let's reduce waste did you know that 70 percent of people in the uk think they do not waste food i'd love to say i didn't waste food but i think that uh it's it's basically the problem is we don't think what food shall i waste today you know it's not on the list is it waste food it's you know i'm trying to find something to eat for my dinner and there's some moldy bag of salad in the way and and we don't look at it because we don't want to think about it but actually there's a lot of talk about supermarkets causing causing food waste in the supermarkets but actually if you look after the farm gate then a lot of about 70 percent of the food waste in the uk is happening in the home that varies a lot depending on what country you're in i won't go into the details but overall over 20 percent of all bread is wasted for example and just to talk a bit more about um the meat if we just were to reduce the amount of meat we're eating to follow the government guidelines then that would help with the greenhouse gas emissions significantly so the government guidelines currently say a maximum it's not it's not a requirement it's a maximum of 70 grams of um of meat per day so this is uh you know this is health guidelines for health reasons there's some pretty cool things you can do this i'm not advocating any particular i don't get money from these people i'm just think it's really cool and that there's lots of technology that can help reduce greenhouse gas emissions we can have less greenhouse gas emissions intensive foods maybe even lab milk there was a big announcement last week that these guys are now selling ice cream uh that they've used uh they're making milk proteins in in the lab uh using a kind of yeah effectively kind of yeast uh but in looking into the future what's going to happen uh in the future what will we be eating hands up if you've ever taken vitamin tablets lots of people what if we really needed to get our nutrition for the minimum greenhouse gas emissions what would we invent maybe we would invent something which is basically a vitamin tablet and what if it was some sort of grey goo like in some of the science fiction films and that was the lowest greenhouse gas emissions food we could think of i think that probably would be the lowest greenhouse gas emissions way to get our nutrition how do people feel about that you may think it's very efficient and easy to drink some great gray goo and there are a number of products available which uh which you can drink and get all your nutrition um there's also very cool things you can do with other nutrition sources anybody know what's in this picture insects very good so have you ever eaten a pink marshmallow uh there's a no i'm not a lot of people only up to this okay so if you bought a regular pink marshmallow that contains something called cochineal which is these bugs here are living on cacti if you grind these up it makes a lovely pink coloring which is natural so that's great news it means you've probably you've already eaten insects through your marshmallows there's a number of products available we've been giving away free insects over there it's probably the lowest greenhouse gas emissions source of animal protein that you can get i'm just going to put a shout out to this incredible magazine if you've got kids or grandchildren or anybody that has access to giving kids a really cool science magazine that they love that i recommend with pop bang they're not paying me but um we we do we do get it because uh it's great uh and uh you know um you can buy insects if you want to buy insects uh we're giving them away at our stand which we've just packed up i'm afraid but uh it's uh we've given away a huge amount of of marshmallows as well that went down very well it turned out but you can find out more about all these things on our website so if you go to ggdot.org um which you can also get to from our main website on my back here for our stand uh and and check out what we've got there then you can find out uh more about some of the things that we've produced to try to help tell people and communicate these facts with people about foods so you can play this game climate food challenge you can guess which food you think has the lowest greenhouse gas emissions and you can also play download these food flash cards with information about greenhouse gas emissions for different types of food we've converted it into the equivalent for driving a car the number of minutes driving a car and how much greenhouse gas emissions would that cause and what i like about that is that you can sometimes think well you know there's there's maybe a lot of emissions from something but then actually we often would drive 15 30 minutes without necessarily worrying about the greenhouse gas emissions but that's comparable to eating some of these these things so just to put it a bit into perspective if you're really keen you can even click through to find out all the details of all the research papers that we got these numbers from in the academic literature i feel really keen so looking ahead what would we like to see we'll sign up to our mailing list and then you can find out about new things that we produce that might be useful and fun to learn about greenhouse gas emissions i was on a panel a discussion yesterday about labeling of foods and i'd love to see you know the best response i get to showing people these cards is this is nonsense there is not one number for a piece of ham right there's not one number because it depends on many things it depends on how long the pig was alive for it depends on how the manure was managed it depends on how it's processed depends on where it's coming from so there's a lot of details which are different for different ways of producing food and ultimately we need food food producers to tell us this detailed information and i think that'll be my dream would be for people to demand this information to be provided by food producers um i'd love to see some sort of um labeling on products so that we don't have to you know go to the academic literature to tell you these numbers but you get the real numbers for the exact way that each food is produced i'm currently writing a book on food and climate change which hopefully will come out in the coming year there's an amazing book you can already read about energy which some of you may know already um written by this fantastic person david mackay and i'd love to see something akin to the 2050 energy calculator now called the makai calculator after david mackay for food so please sign up to our mailing list and i'd love to hear your questions on what i've just talked about thank you very much [Music] thank you okay thank you very much sarah uh any questions oh yeah hi thanks for the talk just uh an interesting but just question really there's a lot of focus on higher welfare animals that kind of thing uh people looking at like rare breeds old breeds older versions of pigs that we used to have in this country as opposed to the commercial pigs yeah a lot of stuff a lot of food comes from actually are they worse for the environment okay so our higher welfare animals worse for the environment and older breeds okay so there's a few issues there so the longer animals are alive for the more greenhouse gas emissions they produce so having higher animal welfare and reducing the number of sick animals does help okay so this is this is this is you know a win all round um older breeds um i don't see why that i don't know any studies looking at older breeds i don't see why that would make a difference to most of these things because in terms of the amount of greenhouse gas emissions for example from manure or feed it all comes down to how much the animals eat and how fast they grow i would actually bet that was it was not helpful um because that's one of the things that we breed for is growing quickly for a small amount of food and so that's that's my guess on that but i don't know about older breeds yeah thank you that's a good question hello hi um looking at the um chart that showed the carbon footprint from the different foods that we play probably about 50 of that um if you want to bring it up about 50 of that top section there was from animal agriculture um and also the amount of land that's given over to animal agriculture would that land be better served by growing plants for human consumption rather than animal consumption moving towards a plant-based diet that's a great question yeah so obviously if we all stopped eating meat if we just took all of that out of our diet then we would be hungry so we'd have to fill it in with it all depends on what we replace it with and so as you say for plant-based options we could get nutrition if we are very careful we can get all the nutrition we need from that those plant-based options but uh where are we going with this uh yeah so we've got to be careful if we just if everyone stopped eating drinking milk for example then then there would be a nutrition issue if they weren't being careful about what the hair they replaced it but fundamentally for example for a cow then you need to feed the cow 10 times as much calories as you get from the meat from the cow so is it there is an inefficiency in going and eating our food via animals so if we then were to be able to use some of the land currently used for growing food for animals for something else what would we do with that land so in terms of something some people say how can we help reduce greenhouse gas emissions we already have this amazing thing called a tree which can help suck carbon dioxide out of the atmosphere so if we can have more uh more things like trees and plants generally sucking more carbon dioxide up the atmosphere that would help significantly yeah my question is very similar to what he's just asked i've got friends who are vegans and then trying to push me into becoming a vegan even though i'm more of a moderation is the key so how sustainable is it if let's say 75 of the world population become completely vegan what is the complications or pros and cons of if we all become plant-based eaters for the world and the climate and all that great okay so the vegan question uh yes that's a good question um so in terms of um it is possible to when i first heard about all of this i went vegan i was so shocked and i probably stood by the oven with my jacket potato in there feeling very smug unpacking my suitcase from a transatlantic flight and probably heating up some kenyan green beans which are all you know all vegan my baked beans was wait waiting for me and so it is possible to be vegan and you know not do exactly the best things for greenhouse gas emissions earth rated fruit and vegetables for example cooking methods cooking it up with the oven on a lot with with fossil fuels um that it's possible to be vegan without necessarily reducing greenhouse gas emissions if you have a lot of air freighted fruit for example um but overall if we were to to cut out animal products from our diet if we have the right um b12 you know vitamins um and the vitamin d which is anyway supposed to be something we supplement uh then there's there's there's not there's not a major problem with that hi hi you didn't say anything about goats good question yeah so when i first saw this about the milk i'm like where else can we get milk from you know so i started to do a bit of research on this turns out unfortunately goats also are ruminants i'm sorry to bring this to you so there's a lot of other animals that produce milk however pigs do produce milk but you have to alternate which teat it comes from every 30 seconds and pigs don't like being milked so don't do that i've looked into other options donkeys and uh horses also produce milk and they're not ruminants so i don't really foresee horse cheese taking off but you know it would be lower greenhouse gas emissions unfortunately got time for one more question thank you thank you um i'm quite interested in a future that involves um a diet incorporating insects and one of the concerns i have about lots of people becoming vegan and i'd be interested to know if you're aware of any research into this is that i understand that a lot of soya is grown in the amazonian area or in the equatorial rainforest and that growing soil and producing soya is now the main cause of equatorial deforestation and i think sometimes people are quite quick to ignore that or not think about it or not look at where the soil is coming from i'm just interested if you'd look to integrate quality research yeah absolutely so that's a great question so um a lot of people are concerned about eating soya when it when it is true that a lot of deforestation is currently happening to produce soy most of the soy that is produced is fed to animals soy is an extremely efficient way of producing protein from the ground you can if you if you need to if you want to eat insects the insects have to eat something and one of the kind of protein sources you could feed the insects could be soya but they have to eat something so in terms of greenhouse gas emissions uh it's soya is is not a problem in itself it's the fact that we're having we're growing a lot of soya to feed to animals which is a very inefficient way of us getting that protein from the soya sadly that's all we've got time for so please give sarah another huge round of applause thank you

Channel: bluedot festival

Views: 315

Rating: 5 out of 5

Keywords: bluedot, festival

Id: 3xqFeoXyaCA

Length: 43min 23sec (2603 seconds)

Published: Sun Jul 26 2020