by Brett Glencross, IFFO, London, UK
Ahead of the recent 21st International Symposium of Fish Nutrition held in Puerto Vallarta, Mexico, IFFO (The Marine Ingredients Organisation) held an invitation-only ‘InFocus Workshop’ to explore the concept of circular feed ingredients and what that means for aquaculture.
The aim of the workshop was to explore issues with feed sustainability and better understand what circularity means.
It was also an opportunity to introduce the European Union (EU) circularity framework, a new EU initiative being championed by the European feed sector [see https://fefac.eu/newsroom/news/fefac-publication-on-circular-feed/].
In this circularity framework a series of four pillars to underpin circular ingredient application were proposed. See Figure 1.
These included:
- Minimising the use of food grade resources as feed
- Minimising the reliance on land use
- Maximising use of locally sourced ingredients and
- Optimising nutritional characteristics of ingredients.
From there the ‘InFocus Workshop’ aimed to examine that framework in the context of how it might apply to the aquaculture feed sector. So, in this regard it began by asking the feed sector how they navigated the complexities of ingredient use.
Navigating the complexity of ingredient use
There are a range of things that the feed industry needs when it comes to looking at ingredients and circular ingredients in particular. To lead this discussion at the workshop, Dr Kyla Zatti of BioMar presented an overview of what criteria the feed industry uses when considering ingredients.
She pointed out that in the last two decades, the global aquafeed industry has shifted from a position of primarily using marine ingredients to one based on plant-based ingredients.
However, this shift had the effect of linking the global aquafeed sector to the social and environmental impacts of agriculture, which resulted in a substantial increase in carbon footprint. More recently the sector has moved to a focus on the application of low-impact raw materials.
However, for them to be used, they need to have significant benefits over alternatives, including both nutritional and environmental considerations.
Some of these novel ingredients, such as low-impact agricultural crops, by-products from food processing industries, fermented raw materials and single cell proteins, even some insect meals have been gaining traction in the sector. Some even hold promise in their capacity to reduce environmental footprints without compromising the nutritional characteristics of ingredients.
Dr Zatti commented that there was a range of six criteria that they examined when considering the use of alternative high-quality ingredients. Among those criteria were:
- Avoid competition with human food supply
- Must be cost-competitive, with the only way an ingredient being considered at a higher price would be when it contains a specific value-added component
- The ingredient needs to have sufficient supply and consistency – targeting a minimum 10,000 tonnes supply
- It needs to have a rich bioavailable nutrient profile, whether that be amino acids, fatty acids, bioactive compounds, vitamins or minerals
- Importantly, it had to adhere to food safety standards which vary by region.
And finally:
6. The ingredient should be low-impact and help the sector shift away from a net loss of resources, such as those associated with deforestation leading biodiversity loss.
She also noted that there were many high-quality ingredients out there that are not defined as ‘100% sustainable’ as they met only some of those criteria but not all. Whereas other ingredients are still on their path to becoming low-impact ingredients, so they can better fit into the sustainable ingredient basket.
Included in that mix, she suggested that the future of aquafeeds was always going to include a combination of ingredients. Plant-based ingredients would continue to be the majority of the diet for the foreseeable future. Though more by-product ingredients and trimmings from fish products, more single-cell ingredients and more ingredients from lower trophic levels, like insects were all on the radar.
She highlighted that demands for sustainability were a key driver for innovation in the present day.
Why nutritional characteristics matter
A key aspect of what the feed industry stipulated was that the nutritional characteristics of an ingredient must fit in with the needs of their target product specifications. This necessitates a characterisation of the ingredient explain Professor Dominque Bureau of Wittaya Aqua in Canada.
Such a characterisation includes an assessment of what nutrients the ingredient brings and also what unintended risks that it brings.
Another critical part of that characterisation is defining the digestibility of the ingredient, so that its inclusion in any diet can be done based on the biologically accessible nutrients, not just the total nutrient supply.
Professor Bureau raised many salient points about the ingredient characterisation process and among them was that we could be doing a lot better in terms defining what we assess. He noted that many of the current assays we use still have their roots in the 19th Century and have not been updated since to any significant extent.
For example, we still base our assessment of crude protein by measuring nitrogen, to which we then apply a conversion factor (6.25) that has little correlation with most of the materials we use and analyse (they range in a true conversion factor of 4.4 to 6.15).
Other analyses, like amino acids, he pointed out, had a range of issues with their analysis that meant that you had to view any data with a certain degree of ‘care.’ Furthermore, the observation from recent studies of the importance of heat-damage impacts on protein sources further added to the story on why being thorough with the characterisation was so important.
This chemical characterisation also extended to the biological characterisation based on assessment of digestibility of ingredients. In the assessment of ingredient digestibility Professor Bureau showed that there was substantial variability even within ingredient types and that this was exacerbated once examined based on the amino acids rather than crude protein.
However, that it should also be noted that accurately estimating digestibility of amino acids of ingredients is fraught with errors, despite that the data is highly valuable to the formulation of cost-effective feeds. The extent of this value was demonstrated by showing how with modern analytics tools that it was possible to examine the cost-effectiveness of different ingredients.
Managing the food/feed grade divide
Professor Margareth Øverland from Norway’s University of Life Sciences considered the question of what we eat and what we don’t and how we can use that to manage the food-feed grade divide.
There were a range of drivers for incentivising the management of this. Included among them were the growing human population, climate change, growing political instability and pandemics disturbing supply chains among others. She noted that there were also political goals in some regions, where a desire to maximise the use of sustainable (preferably local) resources had been clearly stated as a goal by some governments.
Professor Øverland presented a wide range of data including some estimates from OECD and FAO data [see http://dx.doi.org/10.1787/agr-outl-data-en ] on food commodities like grains (mostly cereals), which in 2022 made up most of global agricultural production of some 3.8 billion tonnes per year.
Notably, grains have about 40 percent of their production directed towards feed use, with slightly less going to direct food use. See Figure 3.
Data Source: OECD/FAO (2023), “OECDFAO Agricultural Outlook”, OECD Agriculture statistics (database), http://dx.doi.org/10.1787/agr-outl-data-en
Forecasts by the OECD and FAO also suggest that this use ratio is not going to change much over the next decade, despite that global production is expected to burgeon to 4.24 billion tonnes per year. Contrasting the grains example, she also showed how the production of single-cell proteins, such as filamentous fungi, could be grown on low-value forestry side-streams. Thereby providing feed products with no direct connection to human food consumption at all.
Not only did this reduce the food-feed competition, but for regions like Scandinavia it also helped facilitate the development of locally-produced feed resources for aquafeeds. Biological trials so far had shown much promise.
There were also options to repurpose pre- and post-consumer food waste streams into high-value protein and energy sources for aquafeed using options such as insects, microbial bioconversion and even the use of fermentation processing to increase the value of crop by-products.
While in some instances such use of food waste from our food supply chain already exists, in other cases it remains to be implemented and/or faces regulatory barriers. See Figure 4.
In other cases, it has been suggested that legislation should be introduced to restrict the use of some products in a circular-feed context. She wrapped up her presentation by saying that the solution to the feed raw material challenge lies in fostering a circular feed system, utilising nutrient recycling, waste streams and waste gases to optimise bioresources while advancing a sustainable circular economy through re-evaluation of legislation.
Searching for sustainability
IFFO’s Dr Brett Glencross spoke on sustainability and how it is growing in importance to the feed sector.
However, he also noted that many sectors in recent times had been making calls of “being sustainable” because of what they produced and that without evidence to substantiate such claims, that this was considered ‘greenwashing.’ This had come to the point where regulators were introducing legislation specifically designed to limit what could be claimed as being sustainable.
Core to that was going to be the need to apply a system of metrics that allows for cross utility of comparisons, such as life cycle assessment (LCA) analysis, which was already being managed by a Product Environment Footprint Categorisation Rules (PEFCR) framework in places like Europe to ensure that all sectors followed the same rules.
In addition to the PEFCR framework, the establishment of the Global Feed Lifecycle Assessment Institute (GFLI) to act as an independent repository with standardised database and tools and now has close to 1500 ingredients in its Version 2 database.
LCA has emerged as the most accepted method to objectively assess the range of environmental effects assignable to products and services. It works based on collecting data associated with:
- Inputs (resource use) / Outputs (emissions)
- Designated material flows
- Assigned environmental costs
LCA also assesses impact throughout value-chains, recognising that environmental impacts do not just occur on the production unit and notably captures many different types of impacts in addition to better known ones like carbon-footprint (climate change potential), land use and water use. While databases like those of the GFLI are useful and help establish ground rules by which LCA analyses need to be done, the collection of primary data from ingredient suppliers is increasingly being sought after by feed producers as values for many ingredients can vary markedly based on their specific production systems.
This reinforces why the adoption of circular approaches to ingredient production are becoming increasingly important.
However, such approaches require clear process mapping and design for resource use efficiency and recovery steps to optimise their potential for producing products with the smallest footprint. See Figure 5.
The role of animal breeding
Usually, when running a workshop with a group of nutrition experts, the focus is squarely on the nutrition. But the group did also explore another dimension and that was whether we change the feed or change the animal though better breeding?
To talk about this, Dr Vikas Kumar from the University of Idaho in the USA presented on some of the work that they had done on breeding rainbow trout to better utilise diets based on soybean meal.
Typically, in those studies the strains of fish were selected to grow rapidly and efficiently when fed all plant-protein feeds containing up to 55 percent soy products. These strains contrasted the unselected trout that exhibited 10-15 percent lower growth and feed efficiencies than selected trout when fed those same plant-based diets.
Analysis of metagenomic data obtained from the same experiment showed that there was a host-diet effect on the microbial ecology of the distal intestine. This supported the hypothesis that utilisation of plant proteins may be linked to the function host-gut microbiota.
Why part of the answer may involve ‘Thinking outside the box’
The workshop also considered the concept that not every circular ingredient needed to provide direct nutrients. This concept was presented by Dr Cedric Simon from Australia’s CSIRO, who introduced an example of some technology they had been developing that involved the use of waste-streams to produce a microbial biomass.
In this case study, a series of patented products called NOVACQ™ and NovaqPro™ were introduced.
These products, based on microbial biomass production from sugar-cane waste streams, were shown not to be nutrient sources per se, but rather natural stimulants that accelerated the growth rates of shrimp and improved the efficiency of the use of the existing dietary nutrients. In some cases, improvements in shrimp growth rates of close to 60 percent were observed (https://doi.org/10.1016/j.aquaculture.2023.740176 ).
It was mentioned that the specific mechanism of the product remained something of a mystery and they were still searching for those unknown unknowns, but that the evidence so far implicated that there was a combination of factors involved.
The case study demonstrated however, that the application of some circular biotechnology that increased the productivity of existing feeds was another option to consider in the circular feed story.
Why Communication is Critical
To wrap up the workshop, Professor Luisa Valente from CIIMAR in Portugal spoke on the importance of communication in the messaging of the circular ingredients story. She spoke on the series of challenges and barriers that face circular economy implementation, including a lack of awareness and understanding of many of the issues.
In several instances there has been poor social acceptance in parts of Europe of the use animal by-products in the feed-chain, despite that it occurs and is widely accepted elsewhere around the world.
Such issues with media portrayal of the use of ingredients such as poultry and insect meals as being ‘unnatural’ to feed to salmon has had a legacy of reputational damage for both the salmon farming industry and the retail sector. This issue of managing reputational damage is something that was drawn upon with a focus on how the media, animal campaigning and environmental non-governmental organizations (eNGO) sectors strategise to try and deliver effective campaigns to disrupt animal production sectors. [ https://faunalytics.org/effective-animal-campaigning-current-knowledge-and-guiding-principles/ ]
It was shown that eNGOs regard the most effective animal campaigning as that which maximised suffering spared for every dollar spent using eNGO databases. They highlighted the need to focus on animal cruelty, showing graphic content and comparing farmed animals to companion animals. They also highlighted campaigners to not engage on health or environment-based messages as this may encourage people towards consuming more chicken and fish and was counterproductive to their messaging.
Issues of cultural barriers were also included.
It was noted that everyone has priorities and makes compromises. A good example of this was given based on the example of the choice a vegetarian makes to reduce their impact which was reported as reducing their annual carbon emissions by 440kg CO2-equivalents.
However, it was also shown that flying from Paris to London for a holiday, has similar carbon emissions of 510kg CO2-equivalents. It was argued that the same sustainability impact could be achieved through responsible individual consumption, which could mean someone preferring to a meat-based diet but refraining from air travel or other choices of impact.
But that using diet choices as the only means to justify sustainability was not valid.
Overall, it was shown that effective communication will be essential support the establishment of the circular bioeconomy.
By addressing issues around product quality, price, convenience and communicating those points the sector, would all help build trust. It was suggested that the sector could effectively communicate the value of their circular products or services to consumers, thereby helping manage consumer expectations while also advancing sustainability goals. And that everyone in the value chain had to play a part in that communication.
Published in the August 2024 issue of International Aquafeed.
