Category Archives: New publication

Assessing circular food systems: Fish oil substitute produced from food waste

Imagine that you buy three bags of food at the grocery store and throw away one of them before you get home. Seems crazy right? But the truth is that about one-third of the food produced today is wasted, meaning that a considerable amount of food is produced in vain. Overproduction, cosmetic standards, inefficient logistics and overconsumption are some examples that cause wastage of still edible food along the food supply chain. This waste leads to considerable environmental impact, economic losses and critical social consequences.

Recovering valuable resources and circulating them back to the food supply chain instead of wasting them could lead to important benefits compared to the current system. In fact, using already available resources and reduce waste is considered essential to maintain future food security, enable the transition towards a circular economy and support sustainable development. So, how should we use these resources then? One solution could be to produce a fish oil substitute via microalgae using food waste as feedstock.

Food from waste

Today, aquaculture is one of the fastest growing food-producing sectors globally, and each year we produce about 1-million-ton fish oil rich in the essential fatty acid DHA (found in Omega-3). Since Omega-3 must be obtained through diet, it is often added to food and feed production (often in the form of fish oil) to enhance nutrition levels in dairy, meat and fish consumed by humans. In the beginning, aquaculture was considered a solution to decreased biodiversity and diminished ecosystems, as a result of overfishing. However, the fish oil industry required to support traditional aquaculture is highly dependent on fossil energy and marine raw materials, which leads to depletion of natural resources and ecosystems as the global demand for fish increases. Instead of solving the problem of overfishing, aquaculture has created new ones. At the same time, about 1.3 billion tons of food is wasted globally every year.

In aquatic ecosystems, the essential fatty acid DHA is produced by microalgae and accumulated in fish via the food web. Therefore, one promising solution is to gain DHA directly from microalgae. Research shows that heterotrophic microalgae can be cultivated in bioreactors using volatile fatty acids (VFA) derived from food waste as primary carbon feedstock.

Feeding algae VFA to produce an algae oil rich in DHA could provide multiple benefits in comparison to traditional fish oil, especially since biogas can still be produced alongside. This means that we can produce multiple valuable products from food waste, which would further reduce pressure on natural resources. Producing a fish oil substitute using already available recourses could also support circular food systems and improve global food security. However, assessing and evaluating the environmental implications of new technologies is crucial to ensure that the suggested solutions also support future sustainability.

Environmental impact and loss of biodiversity

This study aimed to evaluate the future potential of DHA produced from algae with a primary carbon feedstock from food waste, by assessing and comparing its environmental impact to that of DHA from Peruvian anchovy oil. The studied systems were modelled as two parallel scenarios to assess large-scale production of DHA: a conceptual Algae scenario and a conventional Fish scenario.

Simplified scenario illustration, created using biorender.com

A life cycle assessment (LCA) approach was used to obtain a holistic quantification of the impact caused by the Algae scenario and the Fish scenario, from the extraction of raw materials via production to finished product. Using LCA indicators at both midpoint and endpoint along the cause-effect chain can provide a vital dimension of total impact to policymakers, the research community and industry. Moreover, including endpoint impact such as damage to ecosystem quality is especially important in systems dependent on biotic resources, such as fish oil production. By definition, biodiversity refers to the variability among all living organisms and maintaining biodiversity is essential for life on Earth. As natural systems and species are dependent on each other, damaged ecosystem quality or loss of even a small number of species could lead to irreversible consequences. Therefore, the endpoint indicator Ecosystem damage was included in this study as a complement to the midpoint indicators global warming, acidification, eutrophication, and land use.

Algae oil VS Fish oil

The main findings were that DHA produced from the Algae scenario inferred lower impact with respect to global warming, acidification and land use compared to the Fish scenario. Moreover, algae oil also resulted in lower climate impact when compared to rapeseed oil and linseed oil, two common plant-based Omega-3 sources. And even though established LCA methods cannot fully account for the total impact on biodiversity, the result showed that DHA from algae inferred lower Ecosystem damage compared to fish oil even when future energy development, improved efficiency, increased energy demand and impact on biotic resources were simulated.

This study showed that DHA produced by microalgae using VFA from food waste can reduce dependency on marine raw materials while also enabling increased resource efficiency by recovering nutrients in food waste for value addition. By using agricultural and food industry by-products to produce DHA, overfishing could be counteracted which in turn would benefit maintained ecosystem quality. Algae oil holds a promising potential for increased sustainability within aquaculture, provided that continued development and optimization of this emerging technology are enabled through active decision-making and purposeful investments. So, recovering valuable fatty acids from food waste and reusing them to produce a fish oil substitute could indeed be a way to increase circularity and sustainability both within aquaculture and the future food system.

Read more

Want to learn more about this project? Then we invite you to read the full article:

L. Bartek, I. Strid, K. Henryson, S. Junne, S. Rasi, M. Eriksson (2021). Life cycle assessment of fish oil substitute produced by microalgae using food waste. Sustainable Production and Consumption, vol 27, pp 2002-2021. doi: https://doi.org/10.1016/j.spc.2021.04.033

Assessing the Circularity of Nutrient Flows in the Okanagan Bioregion, BC Canada

Recent years have seen a steep rise in the interest in ‘nutrient circularity’, ‘closing the nutrient loop’, ‘circular nutrient solutions’, and ‘circular nutrient economy’. As part of a broader food system design project in the Okanagan Bioregion, BC Canada, we took the opportunity to help stakeholders in the bioregion better understand current levels of nutrient circularity and how it could be improved.

The notion of nutrient circularity seems to generally encompass the reduction of nutrient losses – during agricultural production, processing, distribution, and consumption – along with comprehensive recovery of nutrients from organic residuals, for reuse in agricultural production. Nutrient circularity has been defined, for example, with a focus on waste management – as the fraction of nutrients in waste streams that are recycled to agricultural production. This circularity indicator could be referred to as ‘output circularity’. Nutrient circularity has also been defined with a focus on agricultural biomass production – as the fraction of total nutrient inputs that are supplied from waste streams. This circularity indicator could be referred to as ‘input circularity’.

Due to the trade of feed and food, nutrient inputs to crop production in one place may make their way into organic residuals in another place. When assessing the level of nutrient circularity for a bioregion like the Okanagan, simply comparing nutrient need and availability may thus give a distorted picture.

To account for the effect of feed and food trade on nutrient circularity in the Okanagan, our analysis went beyond nutrient need and nutrient availability in the bioregion exclusively. Insofar as nutrient flows relate to food consumption (much of which is imported) and production (much of which is exported) in the Okanagan bioregion, the analysis also included nutrient need and nutrient availability outside the bioregion. This approach enabled a separate discussion of four kinds of nutrient circularity – internal and external input and output circularity – as well as how they relate to one another and to system openness.

Distinction of four types of nutrient circularity – internal and external input and output circularity.

We assessed nutrient circularity separately for nitrogen (N), phosphorus (P) and potassium (K) – for the baseline year 2016 and four scenarios that explore various possible food system futures in terms of the extent of cultivated land, the structure of the food system, and dietary preferences.

List of scenarios considered in addition to the 2016 baseline.

Our analysis revealed that nutrients flow from the periphery of the bioregion towards the center – where population and livestock densities are highest – and from outside the bioregion into the bioregion. For N and P, feed and food trade were found to increase the nutrient availability compared to nutrient need in in the bioregion as a whole by about 50 percent. This comes at the cost of reducing nutrient availability elsewhere. This pattern of nutrient accumulation in the Okanagan can be expected to be more pronounced in 2050 and also apply to K. This is due to the projected population increase and the possibility for increased local livestock production and thus more feed imports.

System openness for the 2016 baseline. Spatial variation across the Okanagan, and for the Okanagan as a whole (INT = internal, EXT = external).

With current organic residual management practices and infrastructure, nutrients recovered from organic residuals are insufficient to meet crop nutrient needs in the bioregion. If nutrient recovery efficiency was increased from current levels to 70 percent – which reflects a conservative estimate of the recovery rates that full-scale recovery technologies can be realistically expected to achieve in the long run – there would be a surplus for N and P in the bioregion but still a deficit for K. If livestock production and feed imports were to be increased in the future, there would also be a surplus for K.

At first sight, the high nutrient availability compared to nutrient need in the bioregion may suggest that comprehensive nutrient recovery may not be needed in the Okanagan. But the nutrient increased nutrient availability in organic residuals is due to system openness associated with feed and food trade. In other words, the increased nutrient self-reliance internal to the bioregion comes at the expense of a reduced nutrient self-reliance external to the bioregion. Our analysis quantified the extent to which different food system scenarios aggravate or mitigate this pattern.

Provided that the goal of nutrient management is to maximize nutrient circularity, across all scenarios, it will be necessary to re-distribute nutrients both within and across the spatial boundaries of the Okanagan. This would help to at least partially compensate for nutrient depletion external to the bioregion in the places from where feed and food are imported. Our analysis estimated the tons of NPK that would need to be moved outside the bioregion to compensate for system openness. Alternatively, if nutrients are not moved from areas where they are accumulating, they are likely to have adverse environmental impacts and aggravate anticipated future nutrient scarcity.

Read more:

Find out more about the Bioregion Food System Project here and read more about nutrient management in the Okanagan in our technical research report. A suite of scientific papers are currently under review and will be released later this year.

Organic and conventional Swedish pork production compared

Organic Swedish pig production according to KRAV’s regulations performed better than conventional Swedish pig production on 11 of 20 sustainability indicators if the comparison was made per kg of pork, and on 18 out of 20 indicators if the comparison was made per hectare. The indicators included both environmental, social and economic aspects. The organic pork had poorer economic sustainability at the farm and slaughterhouse level, but better at retail compared to the conventional one. Climate impact was the same for both systems, while organic production had a higher risk of eutrophication and acidification, but lower for ecotoxicity, negative impact on biodiversity and loss of soil carbon. The social risk for the pigs was significantly lower in organic production, but there are risks for social problems for workers and local communities associated with imported soy and the use of renewable energy.

In a so-called Life Cycle Sustainability Assessment (LCSA), the environmental, social and economic sustainability of Swedish organic pig production has been compared with that of Swedish conventional pig production. The results were calculated per 1000 kg of boneless cooked pork and per 1000 hectares of pig production. For the environmental part, common indicators such as climate impact, eutrophication and acidification were used, but also indicators that are less common such as toxicity to assess adverse effects from emissions of toxic substance (for example as a result of the use of pesticides), effects on biodiversity and the change in soil carbon.

With regard to social sustainability, so-called social life cycle analysis (SLCA) was used in which the “social risk” for workers (in feed production, on the pig farm and in the slaughterhouse), the local community, actors in the value chain, society, consumers and pigs was assessed based on a large number of social aspects on a scale from 0 (no risk) to 100 (very high risk). One aspect for workers was, for example, the risk of child labor. For example this was judged to be low for soy workers in Brazil (applies to imported soy in conventional production). The welfare of the pigs was assessed using 19 indicators that included, for example, the incidence of various diseases and injuries, outdoor access, access to roughage and distraction materials, etc. Data was obtained from previous scientific studies, statistics, reports and from a global database of social aspects (Soca). Risks in different subsystems were aggregated based on how long it took to produce 1000 kg of pork or conduct 1000 hectares of pig production. This means, for example, that the conditions for the pig during rearing plays a greater role than the conditions during slaughter, as the pig spends much longer time on the farm.

Economic sustainability was measured with the indicator Value Added / Life Cycle Costing (VA / LCC). This was calculated separately for the pig farm, the slaughterhouse and the retail. The Life Cycle Cost includes all running costs (including wages) that an operator (farm, slaughterhouse or retail) has for production and the Value Added is calculated as the price an operator receives for pork. The quota thus says something about the profitability of the farm, slaughterhouse and retail.

Life cycle sustainability assessment of Swedish organic and conventional pig production. The organic production is compared to the conventional one (normalised to 0.5 for all indicators) – gray dotted line. The gray solid black line is the organic production if the comparison is made per kg and the gray solid line if the comparison is made per hectare.

The results showed that the organic pig farm performed better than the conventional one on 18 of the 20 indicators examined when the production systems were compared per unit area. Conventional production performed better for the economic indicators for the farm and the slaughterhouse. Although the price of organic pork is higher, organic production had higher costs due to it being more labor-intensive and since it uses more feed than conventional production. This means a VA / LCC quota of less than one for organic production, which means that the price the farmer gets does not even cover the running costs. On the other hand, this quota for retail is significantly higher, 27 for organic and 13 for conventional, which signals a high willingness to pay for organic pork among consumers and high margins in the retail sector for both organic and conventional pork.

If the comparison is instead made based on the production of 1000 kg of pork, organic production performed better than the conventional one on 11 of the 20 indicators. In terms of environmental impact, both production systems had the same climate impact, while eutrophication, acidification and consumption of fossil resources were higher in organic production. Ecotoxicity, impact on biodiversity and ground carbon loss were lower in the organic production. In terms of social sustainability, the “social risk” was higher in organic production for workers and the local community, a result of social risks linked to organic soy from China and from accidents linked to renewable energy production. But for other actors, the social risk was lower for organic production, especially for pigs, it was significantly lower in organic production due to, among other things, larger spaces, outdoor access and access to roughage. However, there were indicators for pigs where the conventional system had a lower risk, for example in terms of the presence of parasites.

The authors conclude by stating that LCSA has the advantage of including both environmental, social and economic aspects in the sustainability analysis. Previous LCAs on pork have mainly dealt with the environmental aspects. However, choosing a number of relevant indicators can be difficult and the choice also affects the result, as well as how the indicators are designed and weighed together.

Read the whole study here:

Zira S, Rydhmer L, Ivarsson E, Hoffman R, Röös E (2021) A life cycle sustainability assessment of organic and conventional pork supply chains in Sweden. Sustainable Production and Consumption 28, 21-38. https://doi.org/10.1016/j.spc.2021.03.028

See also this study on SLCA for the two systems but using a slightly different methodology:

Zira S, Röös E, Ivarsson E, Hoffman R, Rydhmer L (2020) Social life cycle assessment of Swedish organic and conventional pork production. International Journal of Life Cycle Assessment. https://doi.org/10.1007/s11367-020-01811-y 

Miljömässiga mervärden med baljväxter som odlas och förädlas i Sverige

Svenska ärtor, bönor och linser kokade och förpackade i Sverige har väsentligt lägre klimatpåverkan än de importerade motsvarigheter vi finner i butikerna. Men om de svenska baljväxterna transporteras långt för förädling försvinner klimatvinsten jämfört med de importerade. Alla baljväxter är dock en mycket klimatsmart proteinkälla i förhållande till animaliskt protein. Att välja svenska baljväxter minskar också negativ påverkan på biologisk mångfald och kan minska användningen av bekämpningsmedel.

Att öka konsumtionen av baljväxter är fördelaktigt både av hälso- och miljöskäl men idag kommer endast en procent av svenskarnas proteinintag från baljväxter. Och trots att ”lokalt” och ”svenskproducerat” är viktiga mervärden för konsumenter så fylls butikshyllorna med importerade baljväxter som transporteras långt. Idag finns heller ingen anläggning för att processa och förpacka baljväxter i tetra i Sverige, utan detta görs i Italien. I en nyligen publicerad studie i tidskriften Sustainable Production and Consumption har vi med livscykelanalys utvärderat fem olika svenska baljväxter (gula ärter, gråärt, åkerbönor, trädgårdsbönor och linser) odlade ekologiskt och konventionellt och sedan jämfört ärter, linser och trädgårdsbönor med vanligt förekommande importerade baljväxter i svenska butiker. I jämförelsen mellan inhemska och importerade baljväxter ingick även transporter, förpackning och processning/tillagning.

Resultaten visade mycket stora skillnader i energianvändning och utsläpp av växthusgaser. Transporterna var avgörande för skillnaderna. Detta gällde särskilt lastbilstransporterna från Italien för tetraförpackade ärter och bönor. Svenskproducerade ärtor som såldes torra och kokades i hemmet hade bara en åttondel så stora utsläpp som importerade baljväxter som processades i Italien. Svenskproducerade ekologiska linser föll också betydligt bättre ut i jämförelsen än importerade linser.

Figur 1. Klimatpåverkan från svenska och importerade baljväxter.

Många av de importerade konventionella baljväxterna har hög användning av kemiska bekämpningsmedel mot ogräs och skadegörare. Flera av de länder som Sverige importerar mycket baljväxter från har dock ingen eller mycket bristfällig uppföljning av användningen av bekämpningsmedel i specifika grödor vilket gör det svårt att kvantifiera användningen och dess effekter. Många importerade baljväxter odlas dessutom i områden där påverkan på den biologiska mångfalden är stor.

Figur 2. Många baljväxter färdas en lång väg innan de når den svenska konsumenten och odlas i områden där höga återstående biologiska värden riskerar att förloras.

Höga hektarskördar brukar ofta ge lägre energianvändning och växthusgasutsläpp. Våra resultat visar att även låga skördar kan ge mycket låg miljöpåverkan om ärter eller linser samodlas med spannmål. Det är välkänt att baljväxter är värdefulla avbrottsgrödor i spannmålsodling och att deras tillskott av biologiskt fixerat kväve innebär viktiga miljövinster i odlingen. Men trots detta odlas baljväxter endast på ca 2 % av den svenska åkerarealen. Mer svenska baljväxter på tallriken är därför förknippade med många mervärden. Slutsatserna från vår studie är att såväl inköpare som konsumenter kan göra skillnad genom sina val.

Artikeln avslutas med följande rekommendationer för en hållbar produktion och konsumtion av baljväxter:
– Odla baljväxterna i en väl genomtänkt växtföljd, gärna samodlade med spannmål, använd fånggrödor där det är lämpligt samt förnybar energi. Minska eller undvik användningen av mineralkvävegödsel.
– Undvik långa transporter med lastbil, transportera baljväxterna torra med båt eller med järnväg, använd förnybara bränslen och optimerade handelsvägar.
– Undvik att köpa baljväxter i känsliga områden med hög biologisk mångfald och konventionellt odlade baljväxter från länder med hög användning av bekämpningsmedel.
– Köp baljväxter torra eller från förädlingsindustrier som ligger så nära slutkonsumenten som möjligt.

Läs mer i: Tidåker, P., Karlsson Potter, H, Carlsson, G., Röös, E. 2021. Towards sustainable consumption of legumes: How origin, processing and transport affect the environmental impact of pulses. Sustainable Production and Consumption 27, 496-508. doi.org/10.1016/j.spc.2021.01.017.

Studien finansierades av Formas och är en del av det större forskningsprojektet “New Legume Foods”. Mer att läsa om projektet finns på följande blogg; https://blogg.slu.se/new-legume-foods/.

The European Union’s hunger for soybean

In a recent paper published in Nature Food we show that halted soybean feed imports into the EU would favour ruminant animals such as cows and sheep over pigs and poultry. We also show that total production of animal-source foods in the EU would have to reduce if animal feed production is not to encroach on land currently used to produce food. Increased uptake of plant foods in EU diets is required maintain supply of nutrients.

The fires that raged in the Amazon during the 2019 fire season was unprecedented in number since records began in 2013. Although the drivers are numerous a paper in Global Change Biology has attributed the increase in fire count mainly to increased deforestation rates. When forests are cleared the vegetation is left to dry before it is burned off to make way for agriculture.

Agricultural expansion where natural vegetation is cleared and replaced with fields and pastures is one of the major threats to biodiversity and releases large quantities of greenhouse gases into the atmosphere. One of the recognised drivers of agricultural expansions into rainforests and other biomes in South America is demand for soybeans. The majority of soybeans produced in the region are destined for export markets. While domestic legal frameworks are important for forest protection, international trade has been shown to be an important driver of tropical deforestation and macroeconomic factors can often outweigh domestic regulations. Demand-side measures that reduce demand for soybean are therefore important to avoid further loss of forests.

Most of the soybean produced globally is “crushed” to separate the vegetable oil from the protein-rich meal. Each kg of soybean generates around 0.2 kg vegetable oil and 0.8 kg protein meal. Most of the revenue from the soybean crush is generated by selling the protein meal which is almost exclusively used to feed animals. This means that it is increased use of soybean meal, and ultimately demand for animal products, that primarily drives up soybean demand which leads to clearing of new areas in order to increase production.

Out of the total amount of soybean (beans, meal and oil) exported from South America around one-fifth is imported into the EU, where the vast majority is used to feed animals producing meat, milk and eggs. For example around 0.8 kg soybean is used to produce the average kg of EU pork, much more than needed for a kg of soy meat or tofu. If rough feeds (e.g. grass and silages) are excluded almost one-third of all protein fed to EU livestock comes from imported soybean. Demand for animal-source food within the EU thereby drives global soybean demand and tropical deforestation in South America.

Soybean is in itself an excellent crop with among the highest yields of protein per hectare, and being a legume, it fixates nitrogen from the air which reduces the need to apply nitrogen in the form of mineral fertilizers. Soybean is also one of few crops that is on par with animal-source foods when it comes to amino acid profile. The huge demand from the world’s livestock industry for cheap soybean does however make it hard to implement sustainable production.

When fed to animals, the majority of nutrients and energy present in the soybean are lost as heat or manure and only a small fraction is in the end retained in meat, milk and eggs that we eat. Redirecting the use of soybean from feed to eating it directly could therefore reduce the demand considerably. This would reduce pressure to deforest new areas and may also make it easier to implement more sustainable soybean production practices.

In a recent paper published in Nature Food we assess how dependant the EU livestock sector is on soybean imports by estimating how much meat, milk and eggs that would be possible to produce without soybean imports, given that use of EU cropland for animal feed production does not increase, which is important to avoid pushing production of food crops outside EU borders with potential negative environmental effects. We found that, depending on scenario for how to use EU cropland, 18-25% reduced animal-source food production in terms of edible fat and protein would be needed to completely eliminate soybean feed imports. Mainly it was the production of pork and chicken that was reduced, while beef, milk and eggs was less affected in the scenarios. To compensate this loss of nutrition to EU diets only between 17 and 22% of soybean that is currently imported to feed livestock would be needed to produce soy meat, tofu or other products for direct human consumption, thus considerably reducing the EU’s demand for land in deforestation-prone regions. Alternatively some land currently used to produce feed in the EU could be used to produce plant-source foods (resulting in the strongest reduction of animal-source foods presented above). In that case it would be possible to maintain supply of fat and protein to EU diets even without soybean imports.

The potentials for reduced cropland demand in South America were found to be large, but results also showed a risk of increasing cropland demand in South-East Asia, which is also a region where large scale deforestation occurs. Reduced use of soybean meal for animal feed results in less soybean oil being produced and if global demand for vegetable oils remain unchanged, this oil would need to be replaced by other vegetable oils. The most likely alternative today is palm oil. In absolute terms, the increased demand for cropland in South-East Asia was small compared to reduced demand in South America, but it is nevertheless an important potential trade-off that need to be considered. In one of the scenarios we explored the potential to increase rapeseed oil production within the EU to avoid this trade-off. Such a scenario would avoid increased palm oil demand, but instead rely on continued soybean imports to compensate for reduced consumption of meat. Which scenario is preferable will depend on how future global demand for different agricultural products develop. If for example transition from fossil fuels is achieved through the use of vegetable oil fuels a scenario with increased vegetable oil production in the EU is likely a good candidate.

In summary, the results from the new study show that there is a lot to gain by redirecting feeds of high food value, such as soybean, towards direct human consumption. To achieve these benefits without risking burden shifting it is however crucial that policies are developed with a holistic food systems approach and target soybean imports, dietary patterns, and livestock and crop production in conjunction.

Karlsson, J.O., Parodi, A., van Zanten, H.H.E., Hansson, P-A., Röös, E. (2020). Halting European Union soybean feed imports favours ruminants over pigs and poultry. Nature Food. https://doi.org/10.1038/s43016-020-00203-7

Soybean use for plant-based products shown in the figure was calculated based on data from the following sources:

Karlsson Potter, H., Lundmark, L. & Röös, E. (2020). Environmental impact of plant-based foods – data collection for the development of a consumer guide for plant based foods. Swedish University of Agricultural Sciences, NL Faculty/ Department of Energy and Technology. https://pub.epsilon.slu.se/17699/1/Report112.pdf

Ercin, A. E., Aldaya, M. M., & Hoekstra, A. Y. (2012). The water footprint of soy milk and soy burger and equivalent animal products. Ecological Indicators, 18, 392-402. https://doi.org/10.1016/j.ecolind.2011.12.009

Mejia, A., Harwatt, H., Jaceldo-Siegl, K., Sranacharoenpong, K., Soret, S., & Sabaté, J. (2018). Greenhouse Gas Emissions Generated by Tofu Production: A Case Study. Journal of Hunger & Environmental Nutrition, 13(1), 131-142. https://doi.org/10.1080/19320248.2017.1315323

Cai, T. D., Chang, K. C., Shih, M. C., Hou, H. J., & Ji, M. (1997). Comparison of bench and production scale methods for making soymilk and tofu from 13 soybean varieties. Food Research International, 30(9), 659-668. https://doi.org/10.1016/S0963-9969(98)00032-5

Ecoinvent v3.6 – Products: Tofu production (GLO) and Soybean beverage production (GLO)

New paper on the methodology behind the WWF-vegoguide

How can the environmental impact of plant based foods be evaluated and communicated to consumers?

In a new paper published in the Journal of Cleaner Production, Hanna Potter Karlsson and Elin Röös describe the methodology behind the WWF-vegoguide presented in another blogpost. The guide was developed in cooperation between the researchers and WWF in a process described in the Fig. 1 below. WWF was the project owner and were responsible for the final design decisions regarding aspects such as which products to include, target audience for the guide, evaluation criteria and thresholds. The researchers were responsible for collecting footprint data, test the evaluation criteria, and provided feedback on the design to WWF. Views on the guide from external stakeholders like consumer and trade organizations were consulted in workshops.

Fig. 1
Fig.1. Process of developing the Vego-guide.
From Karlsson Potter and Röös (2020). J of Clean Prod.

The environmental impact categories to include in the evaluation of the foods were selected from the planetary boundaries framework (Steffen et al., 2015) and the mid-point categories of ReCiPe (Huijbregts et al., 2016) based on a set of criteria including their relevance for plant-based products, importance for guiding consumers, availability of scientifically accepted evaluation methods and data availability. Four indicators were finaly chosen: climate impact, biodiversity impact, water and pesticide use. Thresholds for rating the different product as green star, green, yellow and orange were designed to be aliged with the WWF Meat guide and to relate to the absolute food system boundaries as presented in the EAT-Lancet report (Willett et al. 2019). All products were compared on a per kg basis despite their different functions and nutrient content, which instead were considered by applying different thresholds for food groups, e.g. the protein group was allowed a larger share of emission space as these are more demanding to produce and more valuable in diets than carbohydrates.  

Read the full paper here: https://www.sciencedirect.com/science/article/pii/S095965262034765X

“Less but better meat” – what does that mean?

Meat consumption in the Western world has to decrease and meat production practices have to improve. Eating “less but better meat” is a strategy put forward by a number of institutions and organizations as a strategy for increasing the sustainability of diets in high-income settings. But how much is “less” and what is “better”?

In a newly published comment in the Nature Food journal, Elin Röös together with researchers from the Stockholm Resilience Center (SRC) call for greater clarity on these concepts as misuse could steer in an suboptimal direction.

The estimation of “less meat” could be guided by positive and negative health effect of eating meat as well as the amounts of different meats that could fit within climate boundaries or be produced from biomass not suited for human consumption. A first analysis shows that “less meat” would mean a reduction in meat consumption by at least 50% in the Western world regardless of perspective.

As for “better meat” a wide range of issues need to be considered (see figure below). A focus on just one or a few of these can lead to very varying conclusions of what constitutes better meat and risks overlooking important trade-offs. The authors conclude: “Scientific characterization of ‘less but better’ is crucial for enabling more informed discussionon value-laden decisions and to build consensus on the meaning of the concept, especially as it gains traction with civil society organizations and policy makers.

The study:

Sahlin, K.R., Röös, E., Gordon, L. 2020. ‘Less but better’ meat is a sustainability message in need of clarity. Nature Food 1, 520–522 (2020). https://www.nature.com/articles/s43016-020-00140-5

Research in this area continues in a project called “Less but better meat” – a joint project between SLU and the SRC.

Överskottsmat – till vilken nytta?

Att ta hand om överskottsmat från butiker och livsmedelsindustrin och donera överskottet till behövande är inte något nytt fenomen globalt, men att göra detta för att minska matsvinnet är tämligen nytt. Som ett resultat av detta så har det på senare tid kommit en rad aktörer som på olika sätt försöker hitta vägar för att ta hand om överskottsmaten till olika kundgrupper via olika distributionssätt. Frågan som kan ställas är vilken nytta som den levererade överskottsmaten ger och för vem? I den nya artikeln “Sustainability Assessment of Food Redistribution Initiatives in Sweden” undersöker vi en rad olika distributionssätt för överskottsmat och vilka sociala, miljömässiga och ekonomiska nyttor dessa skapar. Resultaten visar att använda sig av matkassar till socialt utsatta grupper genererar den största vinsten i termer av att minimera växthusgasutsläpp. Att använda sig av överskottsmat för att producera nya produkter visade sig skapa högst social nytta då det undersökta konceptet skapade flest arbetstillfällen (arbetade timmar per kg distribuerad mat). Problemet som samtliga iniativ har är att få ekonomin att gå ihop, då endast två av de undersökta fallen gick med vinst och inte var direkt beroende av extern finansiering.

Photograph by UNT

Food banks that redistribute surplus food from retailers and the food industry to people in need are not a new concept globally, but their connection to food waste prevention is new. As a result, new types of food redistribution units are emerging and diversifying to find new target groups and distribution methods. The aim of a new study “Sustainability Assessment of Food Redistribution Initiatives in Sweden” was to identify and study surplus food redistribution units in Sweden, and then to assess the impact on several sustainability indicators for selected redistribution units, in order to increase knowledge on the types of values these redistribution concepts generate. The methods used for analyzing the scenarios were Environmental Life Cycle Assessment, Life Cycle Costing and Social Life Cycle Assessment. The results showed that providing food bags to socially exposed people generated the largest reduction of greenhouse gas emissions per kg of redistributed food. Reprocessing surplus food to a high-quality end-product was attributed to a high social value, due to job creation effects in the high number of working hours required per kg of redistributed food. With regard to economic impacts, all but two scenarios studied had monthly financial losses and therefore needed other sources of financial support.

The article has been published open access in MDPI resources:
Bergström, P.; Malefors, C.; Strid, I.; Hanssen, O.J.; Eriksson, M. Sustainability Assessment of Food Redistribution Initiatives in Sweden. Resources 2020, 9, 27. doi.org/10.3390/resources9030027

Reflective crops contribute to climate change mitigation

Albedo change can make an important contribution to the climate impact of cropping systems. Albedo is the share of solar radiation reflected back from the ground. It ranges between 5 and 30% for bare and vegetated agricultural land, and can reach up to 90% due to snow cover. The more reflective a surface, the higher its albedo and the greater the potential for radiative cooling and eventually temperature change.

Photograph by Sergio Lorenc

Albedo has increased globally due to agricultural expansion, converting forests to more reflective grass- and croplands. However, deforestation is associated with losses of crucial ecosystem functions including carbon storage and local surface cooling by evapotranspiration. Managing agricultural land to achieve higher reflectivity has the potential to mitigate local heat waves and global warming. Strategies to increase the albedo of croplands include selection of reflective species or varieties, introduction of cover crops, intercropping, residue retention, and delayed or no ploughing.

In a recently published article, we studied how cultivating abandoned land with short-rotation willow affects albedo and evaluated its potential as a climate change mitigation measure. We found that albedo increased from 16.5 to 21.5% on average when fallow land was cultivated with willow, based on three years of field-measured data. These data were subsequently combined with a time-dependent life cycle assessment (LCA) model of bioenergy produced from willow. Here, we included emissions from the production of inputs, field operations, soil, transport and energy conversion.

Simulating processes and emission along the life cycle and impacts on climate over time allowed us to compare the effect of albedo change (cooling) to that of greenhouse gas emissions (warming) and carbon sequestration in biomass and soil (cooling). In sum, the bioenergy system had a net cooling effect because albedo change and carbon sequestration outweighed emissions from the supply chain and soil. Our results over time showcase the different nature of albedo and long-lived greenhouse gases as climate forcers. Albedo change needs to be sustained for years in order to offset the temperature response to a one-off greenhouse gas emission.

The article has been published open access in GCB Bioenergy:
Sieber, P., Ericsson, N., Hammar, T., & Hansson, P.-A. Including albedo in time-dependent LCA of bioenergy. GCB Bioenergy, n/a(n/a). doi:10.1111/gcbb.12682

The environmental impacts from Swedish food consumption exceed the planetary boundaries for the food system

In a new study by researchers from the Food System Group together with the Stockholm Resilience Centre, the environmental impacts of the Swedish diet were benchmarked relative to global environmental boundaries suggested by the EAT-Lancet Commission. To identify local environmental concerns not captured by the global boundaries, relationships between the global EAT-Lancet variables and the national Swedish Environmental Objectives were analysed and additional indicators for missing aspects were identified.

The results showed that the environmental impacts caused by the average Swedish diet exceeded the global boundaries for greenhouse gas emissions, cropland use and application of nutrients by two- to more than four-fold when the boundaries were scaled to per capita level. With regard to biodiversity, the impacts caused by the Swedish diet transgressed the boundary by six-fold. For freshwater use, the diet performed well within the boundary.

Comparison of global and local indicators revealed that the EAT-Lancet variables covered many aspects included in the SEOs, but that these global indicators are not always of sufficiently fine resolution to capture local aspects of environmental sustainability, such as eutrophication impacts. To consider aspects and impact categories included in the SEO but not currently covered by the EAT-Lancet variables, such as chemical pollution and acidification, additional indicators and boundaries are needed. This requires better inventory data on e.g., pesticide use and improved traceability for imported foods.