Tallinn University of Technology

Biotechnologist professor Petri-Jaan Lahtvee plays on the border between fundamental and applied science. In his laboratory the metabolism of microorganisms is studied and microbes are programmed to function as humans currently need. As people currently need to solve large waste problems and produce food without burdening the environment, the yeast developed by Lahtvee and his colleagues does just that: it produces edible fats from wood sugar obtained from sawdust. In the interview, Lahtvee says that the long-term plan is to value "he-whose-name-we-shall-not-name" as food, i.e. the global source of the problem, carbon dioxide itself.

Petri-Jaan Lahtvee laboris

Mari Öö Sarv | Photos: Karl-Kristjan Nigesen

Professor Petri-Jaan Lahtvee has obtained all his research degrees at the School of Mathematics and Science of TalTech and says that he is interested in and passionate about sustainable and environmentally friendly solutions for the production of nutrients, animal feed, materials, chemicals and pharmaceuticals.

Balancing on the border between fundamental and applied science, his laboratory teaches microbes to behave as needed by humans and studies the metabolism of microorganisms. Looking at how ÄIO, a branch company of the university set up by the research group of Lahtvee, produces edible fats from sawdust and along with partners across Europe develops furniture paints to be more natural, you could say that this man is breathing circular economy. Therefore, it is not so surprising when he says that his long-term plan is to refine the source of global problems or ‘he-who-shall-not-be-named’, i.e. carbon dioxide, into food.

Two years ago, when you became a professor in tenure, you said that your goal was to create strong competence for the biological reprocessing of organic waste into food supplements or feed in TalTech, in line with the concept of a circular economy. How has it been going so far?

(Smiles.)  This is pretty accurate. At the university, we have focused on refining industrial by-products to make supplements for fish, dietary fats for humans, and more. We have mostly worked with wood sugars; however, we also test agricultural residues – straw and food waste.

We have selected by-products that are abundant in Estonia, hence the focus on timber. Estonia has a big timber industry and we could of course refine more of the timber – we mostly saw it into logs and export it, a lot of it is also used for heating – but that produces sawdust, which we want to convert into more than just fuel for heating.

A year ago, you also set up a company based on your research.

Yes, I co-founded it with a Brazilian co-researcher, Nemailla Bonturi, who came to Estonia six years ago for a post-doctoral fellowship. Our company, ÄIO, is focused on the production of food from a wide range of by-products with the specific aim of replacing non-sustainable fats. At present, palm oil and coconut oil are the main oils used in vegan products and elsewhere, but these come at the expense of local communities and biodiversity, including rainforests, at a very high environmental cost. Industries are looking for more sustainable and healthier alternatives and we are trying to provide them with that.

It is a very nice idea, but how do you make food from sawdust?!

First, biomass – straw, sawdust, or food scraps – is broken down into its components. Sawdust and straw are mostly made up of three things: lignin and the wood sugars cellulose and hemicellulose. We focus on hemicellulose and use it as a food for microbes, specifically one species of yeast. This yeast was developed by Nemailla for her doctoral thesis and can produce a wide range of oils and fats.

When Nemailla joined our research group, we started to investigate this yeast further and developed a methodology for carrying out the conversion with the highest efficiency. So, the hemicellulose, or wood sugar, is used for producing a yeast which we can use for extracting useful ingredients – oil, omega-3 fatty acids, carotenoids or antioxidants, etc.

Petri-Jaan Lahtvee laboris ämbritäie kalasöödaga
Ämbris on puidusuhkrute baasil toodetud oomega-3-rasvhapetega kalasööt.

So, the secret is the yeast. Can you also feed it something else instead of the wood sugar from sawdust?

Exactly. A distinct characteristic of our yeast is that it can consume a variety of raw materials. We did not want to use sugars that are suitable for human consumption. This special yeast allows us to concentrate on raw materials that are not normally used for food and that are by-products from other industries.

You have just raised one million euros. What are your plans for the future?

First, we want to show that the process we have developed can be scaled up for production – this is the part that has been the easiest to do at the moment because it seems to scale up very well.

Secondly, as this is a novel method of producing food, it must be proven to be safe for humans. This is what we are currently doing. The European Union is and should be very demanding when it comes to food safety. It is a long process, but so far, all the results have been positive and we hope there will be no obstacles.

The third goal is to develop new and even more valuable products. Today, we can produce a substitute for palm and coconut oil, and in the future, we want to produce omega-3 fatty acids and other special fats. For example, when food industry contacts us with a request for fats that have a specific melting point, viscosity, and health properties, then we should be capable of providing fats with the required characteristics.

In other words, you could train and tame your beautiful red yeast to do just that?

Exactly. We are programming it to do what we want.

What kind of residues and by-products are created when you have fed your yeast and got the fats?

The only by-product is lignin. It is extracted from the wood residues at the beginning of the process and directed into the rest of the chemical industry, but there is a little bit of it left in the pulp, and our yeast does not consume much of it. It consumes everything else, and we do not have a mass of waste to recycle. True, a little bit of CO2 is produced in the process, as is always the case with yeasts, but the idea is to capture and use it industrially. This process is similar to making bread dough or beer – brewing beer turns about a third of the barley sugar into CO2, which is what we do.

ÄIO is not your only research outlet to make the world a greener place. Together with other research institutions and companies, you are also looking for more natural solutions for furniture paints. What are your goals and dreams?

It is a major collaboration with three academic and eight industrial partners from Europe, which aims to replace fossil-based ingredients in paints with bio-based ones. The process is the same. We look for ways to produce these ingredients with microbes. We use yeasts and programme them to produce what we need as efficiently as possible. A major German chemical company called Evonik is very interested, as is IKEA that wants to use our bio-based paints on its furniture.

We also monitor product life-cycle analysis, its end of life, and disposal. Our major project will include in-depth analyses to identify the exact environmental footprint of the whole process and compare it to currently used paints.

So, if IKEA paints their furniture with your paint in its factory, you know the life-cycle cost of that piece of furniture to the environment?

Exactly. Furniture has a lifespan and the analysis takes into account what happens to it afterwards.

Petri-Jaan Lahtvee laboris ÄIO näidistega

I have heard many times that the roles of a scientist and an entrepreneur require different, almost contradictory, personality traits. How did your research become a company?

I have always been on the border between fundamental and applied science. I really like fundamental science, but I also like to see its applications and be closely involved in them. This was an opportunity to see, and to show others, the potential of the biotechnological processes we have developed. It is a challenge in itself to move processes from a laboratory to the industry and it keeps me motivated. We had been developing these technologies in the university laboratories for 4–5 years and asked ourselves whether we could commercialise it and turn it into a useful application for humanity. So far, everything has gone surprisingly well. We are waiting for the first major setbacks.

Will you now become an entrepreneur and no longer do science?

I think I will still be somewhere between fundamental and applied science. At ÄIO, we also do science 80% of the time with the aim of developing more new applications. Some of these we scale up and try to introduce for industrial application, but most of the time is spent developing new applications.

Who runs the business then?

(Laughs.) We are. I am sad to say that I myself only get to the lab a few weeks a year and most of the time I am involved in coordination.

Would you like to go back to the lab?

Yeah... At some point I realised that I am a rather bad role model in the laboratory. You need to take your time there, but if you are constantly in meetings, you lose time which impacts your lab work negatively. I also do a lot of bioinformatics, which is a science that suits my schedule better. You have more control over when and how much research you do. When working with micro-organisms in the lab, they control what you do and when you do it.

What is the next thing you want to find out as a researcher?

In the research group, we deal with very fundamental questions, such as how cell metabolism works. When we do experiments, we can see that sugars go in and some substances come out, but our aim is to understand exactly how the conversion happens inside the yeast cells. Metabolism inside the cell is very complex and I have spent all of my 20 years as a scientist working on understanding cellular metabolism. I will continue this work.

How much do vegetable oils made from bio-waste cost? In money, land, water, energy, carbon, health...?

We have calculated how much CO2 we save compared to palm oil and other alternatives, and we also compared the whole plant product, not just the ingredient itself. If we compare it with palm oil, it is difficult to achieve the cheap price point of the latter; however, palm oil comes with a high environmental impact. Even if we include the environmental footprint of our raw wood sugars, microbial production is many times more efficient than palm oil. When we compare it to coconut oil, our aim is to bring the price of our fats below that.

I would not compare it to rapeseed oil, however, as these fats are not substitutes for each other. Fat as an ingredient is usually solid, so our aim is to produce solid fats for vegan products, such as vegetable burgers, sausages, and cheese. At the moment, plant-based products do not taste very good, although there are exceptions, and this is often due to fats. Fats play a critical role in food – they give food its texture and mouthfeel and enhance the taste. However, if we use rapeseed oil in vegetable burgers, for example, the fat will drain out when we try to fry them, leaving a dry piece of protein. That is what our main line of production does – it makes plant-based foods tastier and also healthier.

If we compare the footprint of plant-based sausages with animal-based sausages, then in most cases, they are over 90% more efficient in terms of land and water use and CO2 emissions.

From the health point of view, our product is beneficial because it contains high levels of antioxidants and omega-3 fatty acids, and unlike animal fats, microbial fats do not contain any cholesterol.

But there is another factor besides the ones you mentioned – food security. With COVID-19 crisis and Russian military action, we have seen supply chains disrupted and food prices go up. If you cannot control food production, food security suffers. One of our goals is to be able to build local production.

You do not have a factory yet?

There is no factory yet. We are trying to scale up production in the lab and we also produce in rented premises. Unfortunately, there is no way to scale up biotech production in Estonia – such rental laboratories and equipment are simply not available. In a year's time, we will decide whether to build our own production plant. Today, we want to produce tens and hundreds of kilos to test the product in different areas and applications.

When can we start buying ÄIO products in shops or eating them?

We have geared ourselves as a business-to-business company, so you cannot buy our products from the grocery store. The reason is the size of the impact. I do not know of such a study in Estonia, but in America, for example, more than 50% of commercial products contain palm oil. Our aim is to replace it with an environmentally friendly alternative, which could be microbial fat.

We have over 35 companies from Estonia, Europe, and America on our partner list, and as soon as we can produce something, we send it to them for testing – mostly vegan food, but also confectionery and cosmetics manufacturers.

Petri-Jaan Lahtvee intervjuud andmas

Let’s discuss why it is necessary to make food from sawdust in the first place. How many people could our planet feed if we continued to eat the way we do now?

We are already at the limit – we are clearing forests to increase arable land. This is not sustainable because, looking at the carbon balance, we are already producing vast quantities more than the Earth is able to recycle and forests are one of the main CO2 sinks. In other words, we should not be looking at whether we can grow enough food on the Earth’s surface – even if we could, we should not be doing so because that would release even more carbon into the atmosphere. Therefore, we need to look at how we can shrink farmland without people going hungry. Nearly 80% of global arable land is currently used to grow feed for animals. If we change our diet and start consuming less animal protein, we can already reduce the amount of arable land considerably. We have to take into account that the global population will continue to grow in the next 20–30 years, and that is why we need to find a healthy alternative to animal protein.

If 80% of arable land is used to feed animals for feeding people, then by using that same arable land to grow food directly for people, we could feed a lot more people or we would need a lot less arable land. For example, if we were to produce plant proteins, we would need four times less arable land and the rest could be forests that absorb carbon. However, that is an extreme calculation and we can also find an intermediate option – the situation would improve a lot if we were to cut animal protein by only 50%, i.e. not eat meat every day but just a few times a week.

What are the most environmentally damaging foods?

Beef and lamb have the largest environmental footprint. Chicken and pork leave a slightly smaller one. Beans, which are already much more environmentally friendly to grow, are comparable to meat in their protein content.

To be more precise – according to Our World in Data database, the production of 100 grams of protein creates 20–50 kg of CO2 equivalents for sheep and cattle; 5.5–7.5 kg of CO2 for chicken or pigs, and just 0.44 kg of CO2 for legumes such as peas or beans. As you can see, the environmental impact is tens of times smaller.

But people WANT to eat meat.

There are already a few meat alternatives that taste very good and are healthier, and if they were to become cheaper... My argument is that if plant-based alternatives would be tastier, healthier, and cheaper, then what reason would we have to continue eating such large quantities of minced meat?

The reason may be our mindsets or habits. New and unknown seems scary and a meat-lover might be unwilling to try plant-based and perhaps admit that it is better.

This shift may come with new generations, but I am sure it will come. Today, plant-based alternatives are also more expensive or equal in price to fish or animal fillets.

But what if I am not looking for ‘plant-based meat’ but make a vegetable stew instead?

It does not have the same nutritional value. If we just take a vegetable, then there is not very much protein in it, and if we eat it in large quantities, we get too many carbohydrates. Beans, for example, are a good source of protein, but Estonians are not used to eating so many beans and are not very good at using them in different foods, whereas in the southern regions of the world, they are used in a wide variety of ways and in abundance. Meat alternatives are needed because many people are simply used to eating meat – we already know how to make cutlets and foreign tempeh is not a substitute for grilled sausage, for example.

It turns out that it is easier to teach a yeast to make food from sawdust than to teach a person to give up sausage.

I believe that this changes with new generations because it is really difficult to reprogram people and their habits. However, crises can do it quickly. Hopefully there will never be a food crisis, but if there were, we would probably review our food consumption more easily and quickly. As long as everything is fine, it is difficult to motivate people to live differently.

A half-joking question – if the limits for prescribed cut are reduced in Estonia, how will this affect the raw material of ÄIO?

We are not directly dependent on the prescribed cut. Our aim today is to use by-products, and if these are mostly created by the timber industry, we will use them. It can also be straw or food waste. In the long term, however, our interest is in using CO2 in the air as a raw material.


Plants consume CO2 and make wood sugars. There are algae, which capture CO2 for their growth, and bacteria, which produce either bacterial biomass or substances from CO2. We are working with the University of Tartu, where a laboratory is capturing CO2 and producing simpler molecules from it that we are refining into fats. Similarly, yeast can be taught to consume CO2.

What you have come up with and developed is a very creative approach to food and resources. What other things of potentially high value do we throw away or burn?

That is exactly what we have been aiming to do – we have consciously and scientifically selected by-products that are most common in Estonia. We were involved in the RITA bio-economy project, where we mapped all the waste generated in Estonia. The map indicated clearly that the highest amount of waste is created by the timber industry, followed by agricultural by-products, and then everything else.

The reason for moving towards using CO2 as a substrate as our ultimate goal – in Estonia, we already burn waste to make energy, but we could also capture the CO and CO2 from the incineration and reuse it as a raw material for chemicals, food, etc. In this case, incineration would not be the end of a life-cycle of any material; instead, we would keep them in the circular economy. This is where we are heading. After all, plants do this, but plants are slow.

How else can bacteria be made to work for us? Could some be taught to eat microplastics from the ocean and then give us light and heat?

We are also feeding our yeasts with the ingredients of plastics and tackling how to degrade and reuse plastics. Often, the problem is that separating different materials that are used together is too complicated and costly. Pyrolysis and the capture and reuse of CO2 is the solution.

I think CO2 is where the circular economy is heading. The more efficiently we can recycle it, the more successfully we can develop circular economy. Today, some companies are already doing it and there is an increasing number of them, so the price of CO2 capture is getting cheaper. If the cost of releasing it into atmosphere is higher than the cost of recycling, we will increasingly invest in solutions that can capture it. It is the same with any new technology – it will cost more to develop in the beginning, but if we want to move in that direction, we have to invest.

Petri-Jaan Lahtvee laboris

You are talking about a whole new world. You have described the road to ÄIO as six years of sweat, blood and tears, failures, and trying again and again. How would you know in an innovation process when to try again and when to give up and start something else?

This is an interesting question. I would say that when small steps forward happen all the time, you should keep trying. In my opinion, you should not try to adopt something as your pet project and keep it alive, but rather try to kill projects as quickly as possible. If one of them survives, take it and run with it.

Tell us about some of your successful failures.

It is an ongoing process; these are the daily things you test. For example, you look at which application your development project fits the best. Most of the time, you set yourself a long-term goal and have many ways to get there. In order to find a way that works, you have to start testing methodologies.

Could you also choose a destination where no road really leads?

The laws of nature more or less dictate the framework of what is possible and what is not. Perhaps our ultimate goal is to find out if it is possible to develop bioeconomy in Estonia. So far, it still seems to be feasible. There is also the question of price – oil is relatively cheap to pump, and in biological processes, you first have to process raw material, then create microbes that can refine it, and so on. These are all separate steps and processes and you need to find the most efficient ways by picking the lowest hanging fruit first and moving on to the next as science develops.

For some reason, biotechnology is not very well developed or widespread in Estonia, despite excellent conditions – we have enough molecular biologists trained by universities, but only a few projects have made it from laboratories to commercial implementation. At the moment, we have the opportunity to repeat the success of IT in green transition. They say that green transition will be expensive, but in fact, it will allow us to develop a new industry in Estonia, which is what we should be doing.

Could you give some tips to researchers who are considering bringing their invention to the market on their own but are reluctant to take the first step or hesitant about marketability.

You must believe in the success of the project and have the motivation to work intensively on it for the next few years. 90% of starting companies fail, so it is probably not worth starting with one foot out the door. However, researchers should not be pressured into it and it should not be the only criterion of success, as universities need strong researchers and lecturers focused on basic research and training the next generation of experts. There must be a balance and there are also opportunities to get new ideas out of the university by licensing your own technology or by finding a CEO of a start-up outside the university to take part in the development of the project as a technology manager.