Crises often bring about change. For too long, food waste has been a major contributor to inefficient use of resources and our inability to achieve greater global food security and sustainability.
More than 1.3 billion tonnes of edible food are wasted every year worldwide, which represents about one-third of total food produced and is enough to feed more than one billion people.
The amount and type of food waste varies from country to country. Forty-four percent of global food waste occurs in least developed countries during the post-harvest and processing stages of the food supply chain. The remaining 56 percent of this loss (of which 40 percent occurred in the pre- and post-consumer stage) was attributed to developed countries in Europe, North America, Oceania, Japan, South Korea and China. As a result, the United Nations has considered reducing food waste a global priority and included it on its list of sustainability goals. In particular, the reduction of food waste has significant implications for several of the UN Sustainable Development Goals including zero hunger; responsible consumption and production; Climate action; life under water; and life on land.
Crisis often accelerates existing trends and the Covid-19 pandemic changes the concept of sustainability. The Covid-19 pandemic has caused major disruptions in the food supply chain and caused major shifts in food access, food security and food loss due to changes in food flow and distribution patterns.
Food supply chains are complex and most operate in a “just in time” fashion where minor disruptions can have dramatic consequences. When employees are asked to stay at home, and all businesses except those deemed essential are closed, consumer demand for food shifts from food services (for example, restaurants, hotels, schools, and institutions) to retail grocery stores. Although a sufficient supply of food is available, the existing food distribution network cannot respond quickly to these changes, resulting in increased food waste.
For example, short-term disruption in eating habits during the early stages of the Covid-19 outbreak in Spain resulted in a 12 percent increase in food loss and waste. In addition, an increasing shortage of agricultural and food processing workers caused by illness or fear of illness is causing fruit and vegetable crops to be destroyed, along with the closure or reduction of the processing capacity of animal slaughter plants. Very limited access to ready-to-market livestock and poultry results in an unfortunate need for humane euthanasia and dumping of millions of animals that were originally destined to enter the food chain.
The economic loss from the Covid-19 disruption is estimated to be at least $ 13.6 billion (US dollars) for US cattle producers and $ 5 billion for US pork producers – with 30 percent less meat available to consumers with a projected 20 percent price increase.
In addition to these economic disadvantages, the lack of adequate provisioning capacity for marketable animal disposal necessitates the use of other, less desirable disposal methods which damage the environment and lead to inefficiencies in resource use (i.e., soil, water, nitrogen, phosphorus, labor) while increasing biosecurity risk.
As a result of the Covid-19 pandemic, researchers have proposed to rethink and redefine sustainability as the intersection of economy, environment, society and human health. In addition, a more holistic approach that includes climate, economy and nutrition is needed to increase the efficiency of the food supply chain by reducing food loss and improving the management of food supply chain waste affected by changes in consumption patterns caused by the pandemic.
In fact, the European Union has indicated plans to revise the Farm to Fork subsection of the Green Deal reforms. Now, more than ever, it is time for food sector researchers and experts to accelerate efforts to develop more sustainable and modern food systems by reducing the costs of food waste recovery and reuse in the food chain. However, a very important component of food loss that has not been considered in all of these proposals, which also has a dramatic effect on food security and sustainability, is mortality caused by outbreaks of animal disease.
The African swine fever epidemic in China caused an estimated loss of 220 to 300 million pigs originally destined for the food chain in 2019. This enormous number of pigs represents 25–35 percent of the world’s total swine population.
Due to a lack of infrastructure to manage the disposal of millions of pigs, the ability to recover nutrients from carcasses is impossible, and burial and disposal of carcasses in landfills are used at great environmental costs and biosecurity risks.
In addition, outbreaks of highly pathogenic avian flu in many countries of the world have caused millions of chickens to lose their lives due to death and depopulation. Unfortunately, the likelihood of future disruptions in global food animal production caused by animal disease epidemics is increasing – due to increased global trade and travel, urbanization, exploitation of natural resources, and changes in land use.
The unprecedented loss of food due to disruptions in global food supply chains has created an urgent need to reevaluate the intertwining of resource recovery, environmental impact, and biosafety of multiple food waste streams and animal carcasses to achieve the greatest value. This is important because animal foods provide about one-third of total human protein consumption; but their production requires about 75 percent arable land and 35 percent of grain sources, while contributing about 14.5 percent of total greenhouse gas emissions.
Reorganizing the restoration of nutrients from leftovers and animal carcasses, and recycling these valuable nutrients into animal feed, could provide great opportunities to use less fertile land and rely less on global grain supplies, while reducing the contribution of livestock to greenhouse gas emissions .
Although Japan and South Korea have been at the forefront of recycling food waste into animal feed, countries that produce much greater amounts of food waste (such as the United States and the European Union) have lagged far behind. Concerns about the risk of transmitting bacteria, prions, parasites and viruses are a major obstacle limiting the recycling of food waste streams containing animal-derived tissues into animal feed. This concern has led government regulations to limit this practice in the US and EU.
Adequate thermal processing is effective in deactivating all biological agents of concern – perhaps except for prions from infected ruminant tissue. The great opportunity for the recovery of nitrogen and phosphorus resources from recycled food waste streams and animal byproducts into animal feed has not been fully appreciated.
Therefore, the aim of this review is to summarize current knowledge about the benefits and limitations of recycling various pre-harvest to post-harvest animal food waste sources, as well as retail to post-consumer food waste sources, into animal feed. to achieve better food security and sustainability.
In Swine & U next month, we will further examine options to maximize resource recovery and the value of waste streams when addressing food waste disposal.
Dr. Jerry Shurson is Professor of swine nutrition at the University of Minnesota Department of Animal Science and can be reached at [email protected].