Summary
Lifecycle assessment (LCA) analyses has been developed to address the limitations of the previous metrics and to create more holistic sustainability metrics with traceability across the value chain and greater cross sector harmonisation of metrics. It is a far more complex calculation, and analyses take into account a variety of environmental impact categories, such as global warming potential, cumulative energy use, abiotic resource use, ozone depletion potential, consumptive water use; and land use, among others. To assess these impacts, the analyses do not just cover the production units, but cover the feed ingredients and their processing, through to the on farm production, to processing, distribution, consumption and waste disposal. All these steps use land, water, raw materials and energy, and invariably have impacts that can lead to harmful emissions. The overall aim is to provide a comprehensive assessment of the full (global) impact of food-production and avoid trade-offs or cross-subsidisations of sectors through incomplete sustainability accounting.
You Cannot Manage, What You Cannot Measure
Metrics are simply a basis for establishing relevant goals and measuring progress against them. This allows then you to demonstrate impact, effectiveness, and value against those goals. In effect, you cannot manage something if you cannot measure it.
In pursuit of sustainability in food production systems around the world, various metrics have been proposed, however the one gaining most use over the past decade has been that of Life Cycle Assessment (LCA). An LCA approach to sustainable development aims to compare the full range of environmental effects assignable to defined products and services by quantifying all the inputs and outputs associated with various material and energy flows and assessing how these flows affect the environment.
Figure 2. Linkage between LCA analysis, Sustainable Development Goals and LCA Impact Categories.
To achieve this the compilation of an inventory of relevant energy and material inputs and environmental releases is required. This then allows an evaluation of the potential environmental impacts associated with each of the identified inputs and releases. Part of this process is the characterisation of emissions; whereby different emissions are standardised into equivalents.
For example, in terms of global warming potential (GWP), which is measured in carbon dioxide (CO2) equivalents, one unit of CO2 = 1 equivalent, whereas methane (CH4) has 25x the CO2 equivalent in terms of GWP. Another of the important considerations of LCA is the observation that environmental impacts do not just occur on the unit of production. Impacts can occur throughout the value-chain from raw material extraction (capture), to processing, distribution, consumption and of course at the point of waste disposal (or recycling). Each of these stages requires land, water, raw materials, and energy, and each can contribute to emissions of some kind or other. Another aspect to the LCA story, is that it is not constrained to just carbon footprint, with up to 18 different environmental impacts now being assessable.
Importantly, LCA is increasingly seen as the “mainstream” way to establish environmental credentials. The process of undertaking an LCA analysis though requires lots of planning and data. How you plan and how you collect the data can have important effects on the interpretation. Because of these constraints, there have been various attempts to set some standards on this; the International Standardisation Organisation (ISO) initiated this (ISO 14040 series), the EU have also taken a lead with the Product Environmental Footprint Categorisation Rules (PEFCR) approach and more recently the Global Feed Lifecyle-Assessment Institute (GFLI) was established to be an independent repository with freely available database and tools.
Equitable Comparisons
It has become clear in recent years that aquaculture is making a strategic use of marine ingredients, leveraging the high-nutrient density and palatability stimulating characteristics of those ingredients to underpin the global production of 52 million tonnes of feed. Finding additional ingredients to provide bulk nutrients into the future is a clear and growing need. An analysis of feed formulations across a range of species shows that plant proteins and oils are now providing the bulk of the nutrients in most aquaculture feeds, and this is likely to remain the case for some time. However, recent studies have shown that this use of plant resources worsens the environmental footprint of aquaculture more than if we had stayed with the use of marine ingredients. Underpinning that assertion about what is more sustainable has been the advent of LCA sciences, which allow us to look more holistically at the sustainability story of everything we use and on a basis of a more equitable comparison.
What are the most sustainable options for feed?
When examining ingredients using an LCA approach, among the various alternative proteins and oils now being used and/or considered and we find that their production typically has a high demand for energy, a higher CO2 footprint and uses substantially more land and freshwater, than marine ingredients. So even though they contribute desperately needed new nutrients into our feed-chain, this is not without some environmental cost. The carbon cost of an ingredient as an additional use criterion in feed formulation needs to be considered. This would transfer additional cost to the higher carbon footprint ingredients, while at the same time encouraging the use of those ingredients with a low carbon footprint, monetising that point-of-difference to further encourage production of the low carbon footprint ingredients. This whole issue of sustainability and carbon footprint is going to become increasingly highlighted and sooner or later the carbon-cost will become part of the cost paid.
Responding to the growing demand for protein, there has been a boom in new enterprises promoting insects, single-cell proteins, and microalgae, among others but notably the only circular ingredients with any scale (pardon the pun) are the use of fishmeal and oil from trimmings and by-products. In 2021, this sector of the marine ingredients industry produced close to two million tonnes, clearly putting it in a different league to the newer emerging “novel” ingredients sector. In fact, if we combine the low carbon aspect of marine ingredient production with the “circular” protein strategy we take something that has a pretty good environmental footprint already; low CO2 discharge, low energy use, and little to no reliance land or freshwater, and make it into something super special, an ingredient with superb nutritional properties and an even lower carbon footprint.
No Such Thing as Waste
Circular protein strategies for the feed sector are arguably not a new concept, but more of a resurrection of what historically we always used to do, but perhaps now presented through a different lens of an environmental perspective. Indeed, use of resources as animal feed is seen as one of the preferable options in the food/feed source use hierarchy. With a looming shortage of protein resources, the need for an approach with increasing circularity in resource use, coupled with the application of some new novel tech to supply the bulk nutrients, may be what is required to fill that future gap. However, the challenge here remains as to how we can effectively implement these technologies at a scale to sustain the rate needed to provide those nutrients AND to deliver this at a cost-point competitive in the marketplace based on their nutrient density.
The benefit of by-products
Most LCA analyses, and especially that in the feed sector is now based on economic allocation, with such allocation methods recommended by PEFCR-Feed and GFLI methodologies. However, the primary catch/production of fish for human consumption means that most of the economic allocation is taken by the food portion, even though that fraction often represents less than 50% of the raw material. This means that the lower-value by-products get attributed an even lower allocation of the environmental footprint. So, materials that are already low CO2 discharge, low energy use, with little to no reliance land or freshwater, become even less so.
By embracing an LCA approach to assessing marine ingredient sustainability, the industry will ensure that they remain accountable on a more holistic and widely accepted path forward for environmental footprint assessment moving into the future. By embracing the use of circular protein and oil use, the production of marine ingredients is taking a proactive step to being part of building a waste-free world. Together these elements are all part of a proactive approach by the industry to maintain perpetual improvement. Given the increasing use of LCA sciences provides a clear and structured way to assess sustainability credentials, adding in the growing role of by-product use and its ultra-low footprint, it is all certainly food-for-thought as to why the marine ingredients sector going forward is embracing lifecycle assessment sciences.