Swine & U Column: Food Supply Chain and Waste in Climate Mitigation


By Gerald Shurson, Zhengia Dou, David Gallagan, and Allison Thomson
Originally printed in The LAND – as September 17/September 24, 2021 Swine & U column

The food supply chain in the United States has been actively partnering with farmers and ranchers to reduce the environmental impact of agricultural operations in the United States over the past 15 years. Food supply chains from the field to the plate are complex, with many different arrangements ranging from direct contracts between growers and food brands common in specialty crops, to the large-scale commingling of commodity grains used in food, feed and fuel that makes traceability of food products back to an individual farm challenging.

The private sector has been taking on this challenge in order to meet environmental commitments, including corporate objectives and science-based targets to reduce greenhouse gas (GHG) emissions, increase soil carbon sequestration, and improve soil health.

Commitments to reducing emissions from food production must include an accounting for on-farm production of the raw ingredients and interventions that reach a diverse community of private landowners and managers. To meet these commitments, grower organizations and the food supply chain are actively working to engage farmers in projects and programs to accelerate the transition to more sustainable and regenerative farming practices such as reductions in tillage, increases in rotation complexity and introduction of cover crops and grazing, that are collectively referred to as “climate smart” (Lipper et al. 2014).

This definition means that the practices either help to mitigate climate through emissions reductions or carbon sequestration or that they make farms more resilient to the impacts of climate change. Private sector efforts involving corporations in the food supply chain to advance adoption of climate smart agriculture have included piloting science-based approaches to measuring outcomes and reporting on progress, engaging growers in on-farm research and trials, testing digital technology for measurement (Thomson et al. 2019) and investing in development of voluntary carbon markets.

This experience provides a robust foundation for learning about successful strategies to engage and support producers in making practice changes. While much has been learned, there are significant limitations to the scope of voluntary programs related to the reach and influence of the corporations to influence farmers and the information available on creating successful interventions (Friedberg 2018).

The scope of the research necessary to move past some of these limitations requires investments that would collectively benefit all farmers and actors in the food supply chain. Government-supported research programs in rural sociology, agricultural economics and social sciences that seek to understand the barriers to adoption and sustained use of regenerative and climate smart agricultural practices in diverse farming communities is needed.

Providing a roadmap and establishing public-private partnerships will increase the effectiveness of private sector efforts. Reaching and enrolling farmers to participate, gathering sufficient data to measure or calculate GHG emissions and soil carbon, and appropriately incentivizing practice changes that improve these outcomes could all be enhanced with evidence-based strategies for collective action.

Another barrier is in the efficient and accurate calculation of environmental outcomes and monitoring for improvements that is necessary to ensure interventions are achieving the desired goal. One major obstacle in this work is the limited availability of field-based research data for widespread calibration and validation of tools across the full scope of farming systems and geographies of U.S. agriculture.

Enabling field research on climate smart agriculture practices around the country, and standardized data as well as metadata collection protocol are necessary. In addition, a centralized data repository to ensure field data is readily available for use by model- and decision-support-tool developers will improve the accuracy of GHG emissions and soil carbon estimates from farms. Consequently, science-based feedback will be available to producers about the practices most effective at reducing emissions from their operations.

Food waste and carbon footprints

With roughly one-third of food produced for humans lost or wasted, our ability to end hunger, protect the environment, conserve natural resources, and mitigate climate change impacts is greatly undermined. GHG emissions attributed to food loss and waste (FLW) account for 8–10% of global anthropogenic emissions (UNEP 2021), making it the third largest emitter behind China and the United States if FLW were a country (FAO 2013).

In addition, food loss and waste has dramatic effects on depleting finite essential resources such as phosphorus (Leinweber et al. 2017), and aggravating nitrogen pollution problems (Reis et al. 2016; Sutton et al. 2021).

The UN Sustainable Development Goals (SDGs) Target 12.36 calls for halving per capita food waste at retail and consumer level by 2030 and reducing food loss along the production-supply chain. Reducing food wastage and re-purposing non-preventable food loss to the highest value possible will directly or indirectly address carbon, nitrogen, phosphorus, and all 17 of the UN Sustainable Development Goals.

Food waste prevention is at the top of food recovery hierarchy in addressing food’s climate and sustainability challenges. However, progress in waste prevention has been extremely slow. Except for a few bright spots, the world overall is far behind where it needs to be toward achieving SDG Target 12.3. In the United States, food donation and various food rescue efforts helped to save up to 2 million tonnes (4.4 million pounds) of food from being wasted (Dou et al. 2018). The amount is significant for helping food insecure families, but very small compared to the magnitude of the problem–60 million tonnes (132 million pounds) of edible food is lost/wasted at the consumption stage annually (Buzby, Wells, and Hyman 2014).

The reality is that cities in America and elsewhere must deal with large streams of food waste generated throughout the food system, particularly from homes, restaurants, wholesale and retail outlets, now and for the foreseeable future. The question is: How can societies manage the food waste streams in ways that extract the maximal value while alleviating climate and environmental burdens?

Urgent Action is Needed

A national framework that focuses on creating and/or expanding commercialization of food waste recycling options that are appropriate for specific waste streams, with the goal of optimizing resource recovery; reducing carbon, nitrogen, and phosphorus footprints; and mitigating climate impact.

  • Develop and implement government policies and entrepreneurial incentives at local, state, and national levels that encourage investment and commercialization in higher value food waste re-purposing and nutrient recovery practices (i.e., conversion into animal feed).
  • Engage FDA/CVM in addressing biosafety concerns including (1) applying FSMA regulations to food waste for animal feed, (2) re-evaluate the applicability of the Swine Health Protection Act, (3) re-evaluate current thermal processing conditions to ensure compliance with the highest biosafety standards, (4) define low bio-hazard food waste stream sources, and 5) develop science-based Hazard Analysis and Risk-based Preventive Controls for food waste processing facilities.
  • Invest in research and technological innovation to establish LCC reduction credits of food waste recycling options; document socioeconomic, environmental, and climate impacts of the various options; and foster technological integration for greater synergy and less tradeoffs.
  • Create educational programs and promotions to change societal perceptions from thinking that food waste is “garbage” toward considering it as a valuable “green” resource for soil amendment/fertilizer (composting), biogas (anaerobic digestion) and animal feed.

This article is part of a larger paper composed by members of the Council for Agricultural Science and Technology (CAST): The Science Source for Food, Agricultural and Environmental Issues. The entire paper, “The Role of Agricultural Science and Technology in Climate 21 Project Implementation” June, 2021 can be accessed at this link: https://z.umn.edu/CASTjune2021

Gerald Shurson is a professor in the University of Minnesota’s Department of Animal Science. Dr. Shurson focuses on the area of swine nutrition with a wide variety of related research topics. He can be reached at shurs001@umn.edu.