How many times have you opened the fridge to find molding cheese, wilting lettuce, leftovers you forgot about, or eggs too old to use? You can easily throw these items away to make room for the next trip to the grocery store or to the market or to wherever you buy food. This stuff isn’t that expensive, so it’s not a big deal to get rid of it. It’s all so normal that we may not give a second thought to the fact that we own a fridge, that we have food to store in it, and that access to more food is relatively easy and cheap. But this is quite a feat, one that isn’t even imaginable for so many other individuals and families around the world. Beyond the obvious privilege, we may not realize that we’re entangled in a larger problem that’s haunting the global food system, not only in the Global North but also in less developed areas: food waste.
The waste of food that is left uneaten, discarded because it’s spoiled, or lost in the supply network because of inefficiencies in production and distribution offers a particularly interesting entry point to start examining issues of sustainability in the food system. Sustainability refers to approaches that balance the use of resources in the present with their long-term availability in the future. Although food waste is just one aspect that needs to be dealt with to address sustainability, we experience it tangibly on the one hand, especially in terms of the money we lose and the guilt we may (or may not) experience. On the other hand, we are discarding not only individual items but also all the resources, energy, and inputs that go into producing them. Preventing waste means more than just shopping smarter and making sure that we use everything we buy. It requires dealing with problems that plague our global food system and need to be tackled in their totality and in their complex interconnections. Starting from uneaten and discarded food, this chapter will examine the environmental features that affect sustainability in the food system (waste management, water and air pollution, soil degradation, deforestation, conservation, energy, greenhouse gas emissions), as well as their social and economic aspects (human health, justice and equality, labor exploitation, accessibility, efficiency). All these elements need to be observed within the broader framework of our time’s most critical emergency, climate change, which already has an impact on what we grow and how we grow it. Not only does climate change affect food production, but food production itself also contributes to climate change.
The waste of food that is left uneaten, discarded because it’s spoiled, or lost in the supply network because of inefficiencies in production and distribution offers a particularly interesting entry point to start examining issues of sustainability in the food system.
Measuring food waste is not easy, and debates have developed on the methods used to gather and analyze data.1 The FAO estimated that in 2007 about 1.6 billion tons out of a total of six billion tons of food produced went to waste globally, creating a carbon footprint equivalent to 7 percent of all global emissions.2 A recent study found that US consumers on average waste about a pound of food (30 percent of daily calories available) every day. Such food is grown on thirty million acres of cropland every year, equivalent to 7 percent of annual cropland acreage.3
The roots of the issue go well beyond the lack of planning or the carelessness of consumers. Waste is embedded in supply networks, starting from agricultural fields and other production sites. These dynamics are particularly urgent in developing countries, where the lack of adequate infrastructures, investment, farmers’ education, and technical personnel is glaring. Waste may occur in countless ways. Lack of coordination may prevent parts of crops from being collected. Prices may drop so low that farmers would lose money if they invested funds in harvesting. Products may be exposed to weather or pests during transportation or warehousing, or farmers may not have sufficient connections to markets. Produce that doesn’t meet the quality standards–sometimes including aesthetic requirements—imposed by small and large buyers is often discarded. Milk may go to waste because of poor refrigeration during collection or scarce hygiene in dairy plants. Further losses happen during distribution, storage, and sales. Defective packaging also can be a culprit.
Supply networks in the Global North are not immune from food waste. Overproduction may push authorities to impose quotas and destroy crops and products to keep prices at levels that ensure acceptable revenues to producers. EU citizens are routinely angered by the destruction of milk, tomatoes, and oranges, among other products, which seem particularly offensive when many fellow citizens do not have enough to eat. Consumers may not want to buy fruits and vegetables that do not look perfect, with the consequence that unsold produce may be thrown out even though it’s perfectly edible. Shoppers may be confused by “use by,” “best before,” and other information on packaging, refusing to purchase food that is still safe. Stores, supermarkets, restaurants, schools, hospitals, army messes, and cafeterias may throw out unused food. In fact, they may not be allowed to store cooked food for consumption at a later time or for distribution to charities because of safety regulations.
Such breathtaking waste has generated practices that manage to take advantage of it. Underprivileged populations in large urban centers that do not have other opportunities to feed themselves routinely search for usable materials and food in landfills. Gleaners roam fields to gather whatever is left after the harvest. At times, reactions may have political undertones. Dumpster divers salvage discarded food items from garbage containers as well. Freegans avoid engaging with the monetary economy and embrace alternative strategies, such as squatting and “guerilla gardening” in city parks or abandoned spaces.
Social discomfort with food waste, inefficient but also unethical and unsustainable, is stimulating efforts to limit it at all levels of supply networks. Organic waste can be composted into fertilizer to improve agricultural yields or “digested” in technological plants to generate biogas that can be refined and used as fuel or converted into electricity. Food oils are recycled into biodiesels to replace fossil fuels, creating a market for the acquisition and use of used frying oils from fast foods and restaurants. Start-ups are finding new ways to turn leftovers from food manufacturing into inputs for food and nonfood products: old bread is fermented into beer, and used barley from beer brewing is ground into baking flour. Orange peels from juice factories become textiles, and grape leftovers from winemaking are processed into faux leather. “Ugly” or damaged fruit can be squeezed into juices, turned into jams and sorbets, or dried and powdered to add flavor to seasoning mixes. Chefs are rethinking menus to limit food waste and use all edible parts of ingredients. Innovative packaging materials change color when the content turns bad, helping consumers avoid throwing out food that is still good. Software using demand-modeling algorithms can generate reliable projections by factoring in demand variability, can improve logistics, and can reduce waste by fine-tuning on-time transportation and communication among the actors in a supply network. Such technologies are particularly effective for perishable goods such as fresh fish, vegetables, and fruits. Apps allow restaurants and stores to send information about unused food to charities and other organizations that can make good use of it.
Creativity and innovation definitely contribute to mitigating the effects of food waste that are visible to consumers—and thus are perceived as socially and politically relevant. However, to deal effectively with the issue, it’s necessary to concentrate efforts on the complex relationships among the environment, production, and society at large. Beyond optimizing the manufacturing and life cycle of a single product, already a relevant and worthy endeavor, the next step is to examine the flow of energy and materials across supply networks. Such complexity demands a change of mentality and a shift toward systemic perspectives. Food is connected to water, energy, and other inputs that require infrastructures, transportation, and other technologies, which in turn entail broader environmental and industrial policies. Climate change, the most urgent challenge that connects all these issues at a global level, needs intensive international cooperation beyond the involvement of national governments, local communities, small and large businesses, producers in all sectors, and consumers. However, as all these stakeholders address the issue with different values, goals, and priorities, any decision about climate change turns into a political challenge.
These tensions also intensify because sustainability cannot refer to environmental protection and resource conservation only, but also needs to include long-term economic viability and social equity. As this implies addressing causes rather than just mitigating consequences, such an approach requires public policy interventions, as well as changes in corporate decision-making processes.4 These dynamics indicate that the very concept of sustainability is predicated on a collective perspective because it indicates forms of growth and development that embrace limitations on today’s consumption to ensure the ability of future generations to meet their own needs.
Considering sustainability as a priority while ensuring enough food for the growing global population leads to reevaluating the epochal transformations that have been taking place in food production. Mechanization, intensification, and logistic innovations (see chapter 2) have enormously increased agricultural yields and the availability of affordable food worldwide. However, the focus on increasing production through technology came at a price, at times causing the loss of small farms and the devastation of rural communities. The expansion of agriculture to areas that were not particularly fertile required massive irrigation, the intensification of cultivation, and the search for increasingly higher yields. These changes took place together with a staggering upsurge in the use of chemicals, from fertilizers to pesticides and herbicides. Such dynamics were exported to developing countries starting in the late 1960s under the name of the green revolution (see chapter 5).
In the nineteenth century, the traditional use of manure from local farm animals had already been replaced by more efficient sources of nitrogen to replenish the soil—in particular, guano, the excrement of seabirds and bats accumulated in great quantities on islands off the coast of Peru, as well as in the Caribbean and elsewhere. Due to its remarkably elevated content of nitrogen, phosphate, and potassium, guano constituted such an important resource despite the costs of collecting and transporting it that disputes for its control turned at times into wars. However, its relevance waned after the Haber-Bosch process of industrial nitrogen fixation was invented in the early 1900s to produce ammonia-based fertilizers (ironically, the same technology was also used to develop chemical weapons). New arsenic pesticides and DDT were introduced, replaced over time by organophosphates, pyrethrin, and triazine, among others. In fact, DDT was proven to be hazardous for humans and to affect the reproduction rates of some bird species. The environmental movements that developed worldwide in the 1960s and 1970s, fueled by books like Rachel Carson’s Silent Spring, published in 1962, led to the introduction of legislation that reined in the indiscriminate use of synthetic pesticides.
In the Gulf of Mexico, runoff from agricultural areas in the Midwest has created a dead zone in which lack of oxygen due to algal growth is destroying marine life—and this zone is as large as the country of Belize.
Environmental issues connected with agriculture are far from being resolved. Fertilizers and pesticides can be washed away easily by rain. They infiltrate water reserves, pollute rivers, and run off to the oceans, damaging wildlife and stimulating the excessive growth of algae and microorganisms. These residues can suffocate whole ecological systems. In the Gulf of Mexico, runoff from agricultural areas in the Midwest has created a dead zone in which lack of oxygen due to algal growth is destroying marine life—and this zone is as large as the country of Belize.5 New genetically modified crops are now available that are resistant to specific pesticides, like glyphosate, making spraying innocuous for those plants. However, the pesticides’ effects on consumers are hotly debated because chemical residues can be harmful to humans. It isn’t unusual for chemicals to be sprayed while workers are on the fields; they may be unable to protest because they’re undocumented, afraid of losing their jobs, or lacking in political clout.6 Chemical inputs are also widely employed in small farms all around the world, where workers may not be properly trained to use them correctly. The success of organic agriculture is partly a reaction to these concerns. Animal species also can be threatened by artificial agricultural inputs: nicotine-based pesticides seem to be harmful to bees, despite agribusinesses’ claims to the contrary. The global decrease of the bee population is causing concern because bees are the main pollinators for many crops. A market for traveling beehives that are temporarily located where needed has developed to respond to this emergency. These kinds of Band-Aid interventions, however, do not address the global decline of pollinators, a major risk for agriculture.
The worldwide diffusion of mechanization, which cuts labor costs and expedites harvesting, has led to a preference for high-yield varieties cultivated in monoculture conditions, which also respond to the needs of the meat industry’s growing demand for animal feed. Soy and corn have become among the most widely cultivated crops worldwide, but only very limited varieties are used. The expansion of monocultures has streamlined crop production from sowing to growing, collecting, and transporting. It has also caused heavy losses in terms of biodiversity: varieties that provide lower yields or require more manual labor are abandoned. However, a wider assortment of varieties of the same species, each with its own characteristics and strengths, can constitute a form of insurance against the diffusion of pests and diseases, which can have devastating effects if cultivations only include a single variety susceptible to these issues. Richer agrobiodiversity also ensures a greater availability of species that may better adapt to soil salinization, erosion, and depletion, as well as the consequences of changing climate conditions, droughts, and floods. In Mexico, traditional corn varieties frequently have been replaced with more “modern” seeds that are supposed to have higher yields. However, the old varieties had been selected by generations of farmers to adapt to specific natural environments and soils, ensuring a sufficient harvest during dry spells in which the new varieties are not able to grow as expected.
Monocultures also affect the complex ecologies that have evolved around specific species. Coffee is a well-known case. Instead of growing under a shade canopy of mixed native trees that provide a habitat for migrating birds, coffee plants are cultivated in wide, open fields that, in addition to requiring the destruction of wide swaths of rainforest, leave little room for other plant species and for birds that control insect pests and pollinate crops. The production of so-called shade-grown coffee is now supported by organizations that aim to protect both the forest environment and the animals that live in them.
The application of industrial methods to achieve economies of scale is not limited to agriculture. Meat production operations have adopted similar models, which better respond to the growth in demand both in the Global North and in developing countries. The conversion of forest to cattle pasture is among the main causes of deforestation in countries such as Brazil, Colombia, and Costa Rica. Concentrated animal-feeding operations (CAFOs), in which beef cattle, dairy cows, pigs, or chickens are raised in extremely confined spaces, are increasingly common. They have become quite controversial because they tend to physically displace or to push out of business smaller enterprises that may instead favor less constricted spaces for poultry and livestock. The proximity of animals in CAFOs requires the administration of antibiotics to avoid bacterial infections, but the presence of such substances in meat can contribute to the rise of antibiotic-resistant “superbugs” that can’t be eliminated with traditional treatments. Livestock operations also sometimes employ hormones that accelerate the growth of their animals but may have negative effects on consumers’ health. As concerns about antibiotics and hormones grow among consumers, many agribusinesses are taking measures to limit or eliminate their use.
Livestock raised in CAFOs tend to be slaughtered in mechanized plants that constitute environmental hazards in themselves and a threat to food safety if the meat is not properly treated. To keep labor costs low, these businesses at times employ undocumented workers, whose personal safety can be jeopardized by the fast rhythms of production and the use of dangerous machinery. Furthermore, the lack of labor protection and controls can lead to exploitation and sexual harassment. CAFOs may also have adverse consequences on the environment. The huge amount of gases such as methane and ammonia emitted by dense concentrations of animals negatively affects air quality and makes living nearby difficult to bear. Added emissions derive from the fossil fuels used to sow, fertilize, and harvest animal feed, which also diverts land and water from the production of crops for human consumption. Open lagoons in which waste flows to be treated attract insects and other vermin. CAFOs are sometimes built in the vicinities of disadvantaged communities that have little social and political negotiating power to oppose them; members of these communities find themselves stuck in place as the real estate values of their homes plummet. CAFOs also use vast amounts of water to raise animals and keep them clean. If waste and manure aren’t properly treated, dangerous substances, pathogens, and antibiotics can spill over and contaminate both groundwater and surface water in the surrounding areas, ending up in rivers, lakes, and eventually oceans.
Open waters are threatened by the expansion of fish farming as well. Consumers are increasingly more aware of the benefits of fish protein, which comes with little saturated fat and plenty of polyunsaturated fats, such as omega-3 and omega-6 fatty acids. The demand for seafood has increased, supported by improved transportation and conservation technologies. As a consequence, overfishing has decimated wild fisheries. This is an example of the “tragedy of the commons:” individual actors—mostly fishing corporations—race to take advantage of a scarce shared resource in the hopes of making a short-term profit before the resource disappears, regardless of the common good of the community. Luckily, alternative experiences exist in which shared resources are collectively managed through cooperatives that are governed by the users themselves.7 Regulations have been adopted at the national and international levels, imposing measures to limit fishing and replenish the wild fisheries, with partial success. Educational campaigns have focused on explaining seafood sustainability to shoppers, indicating which fish are in danger of extinction or are part of unsound supply networks. Consumers are also encouraged to eat lower on the food chain by opting for squid, mollusks, shrimp, and small fish like anchovies, sardines, and herring. Chefs and culinary professionals are looking at ways to make trash fish, species that aren’t usually eaten, more interesting and appealing.
Although intensive fish farming in both sweet waters and the oceans fills the gap in seafood demand, concerns have been voiced about these practices. Carnivore species require fish feed, partly composed of small wild-caught fish, which exacerbates overfishing: several pounds of wild fish, which could also be directed to human consumption, are used for every pound of farmed salmon. Fish are raised in high concentrations, which increases the risk for disease and parasites to spread and pushes operators to use antibiotics that can eventually enter the environment. As in the case of meat, the presence of antibiotics raises health concerns for consumers, who are often doubtful about the overall quality of farmed seafood. Fragile habitats like mangrove swamps have been destroyed to build fish farms in nations such as Thailand, India, Ecuador, and Costa Rica. The presence of fish farms, especially if concentrated in a small area, can have a negative impact on the surrounding environment because waste can easily get dispersed in the water. In Vietnam, rice paddies have been turned into lucrative shrimp farms, but when an excess of medicinal substances and polluted matter makes the ponds useless, the soil is too contaminated to be repurposed for rice cultivation, an activity that is otherwise culturally and socially central to the traditional livelihood in rural regions.
Ecological damage can occur if nonnative species are unintentionally introduced into the wild. Genetically modified fish are being engineered with traits that ensure faster growth and resistance to the artificial conditions of fish farms. The possibility of such species finding their way into the open has generated anxiety among not only environmentalists but also large segments of consumers that look at GMOs with suspicion. However, seafood farming also can be beneficial when practiced correctly. Raising oysters in cages, for instance, can be sustainable: the oysters filter phytoplankton and excessive nutrients out of the water, while their waste provides nourishment to microorganisms that are consumed in turn by crabs and other sea creatures. Moreover, oyster beds are also being studied as a possible means to counteract the loss of the wetland habitats that used to mitigate coastal flooding.
Raising oysters in cages … can be sustainable: the oysters filter phytoplankton and excessive nutrients out of the water, while their waste provides nourishment to microorganisms that are consumed in turn by crabs and other sea creatures.
The expansion of industrialized agriculture, as well increases in meat and seafood production, have crucial consequences for the health and dietary patterns of consumers, the labor conditions of farmers and workers, and the sustainable use of land, water, and other resources. Research suggests the changing conditions of food production have a direct impact on the global phenomenon of climate change. Although the dynamics of this connection are complex and multilayered, the main drivers have been identified: deforestation, energy use in agriculture, and methane and other gases generated by livestock farming.
Through photosynthesis, plants use carbon dioxide (CO2) to grow. Nevertheless, research indicates that an excess of the gas can compromise the presence of protein, zinc, and iron in edible crops.8 CO2 is among the gases that absorb and emit heat within the thermal infrared range, contributing to the greenhouse effect and raising temperatures around the planet. While the expansion of cultivated crops increases the amount of CO2 captured in vegetation, deforestation to make more land available for agriculture releases large amounts of CO2 into the atmosphere, adding to the emissions from the combustion of fossil fuels. The expansion in the production of biofuels from plants, often supported by government subsidies as a sustainable addition to nonrenewable fossil fuels, also has an impact on greenhouse emissions. On the one hand, the CO2 absorbed by the plants from which biofuels derive may offset the CO2 emissions generated when they’re used as fuel. On the other hand, when additional land is cleared to grow crops for biofuels, CO2 is released into the atmosphere. Whether the overall impact is positive or negative is under debate. Furthermore, energy and fuels are needed for the cultivation of these plants and their transformation into biofuels. As more agricultural land shifts to biofuel production, the prices of edible crops may increase, stimulating farmers to clear more land and causing additional releases of CO2. Such an effect can be mitigated by the production of ethanol from algae, fungi, and nonedible plants such as jatropha, or by using cellulose byproducts from food production, like sugarcane leftovers from sugar manufacturing. Food production—in particular, livestock farming—generates the emission of other gases beside CO2, such as methane and nitrous oxide, which also contribute to the greenhouse effect, one of the main causes of climate change. Moreover, shifts in land use, with their consequent alterations to the distribution of vegetation, influence the reflection of light and heat off the planet’s surface, contributing to a rise in temperatures.
The introduction of new high-yield varieties and technologies, together with the expansion of cultivated land, requires massive irrigation. Today, agriculture counts for 70 percent of the global use of fresh water.9 Drinking water has become a luxury in many areas of the world. Shifting irrigation patterns are likely to affect humidity and cloud circulation in the atmosphere, altering rainfall distribution and indirectly worsening the greenhouse effect. Moreover, irrigation has become a major contributor to water scarcity and the depletion of aquifers around the world. Both small rural enterprises and large agrobusinesses invest in drilling and wells, even if the temporary advantages connected with more water availability are likely to cause long-term problems. Instead of fighting for water conservation in the public interest, governments often adopt policies that reflect the interests of the agricultural sector. For many smallholders, water availability can literally make the difference between life and death. Studies are underway on the optimization of water use through improved crop distribution and more efficient irrigation, while avoiding land use change to extend crop cultivation.10 However, larger corporations usually are better positioned to take advantage of available resources, at the expense of less powerful stakeholders, contributing to vicious circles of inequality.
Climate change could potentially generate benefits, such as greater precipitation, higher temperatures, and longer growing seasons, in areas that were previously too arid and too cold for agriculture. Farmers in upstate New York state now enjoy a longer growing season and the possibility of cultivating more diverse crops. A whole new wine industry is developing in countries such as Poland and Denmark thanks to both the development of grape hybrids adapted to cold environments and a warmer climate. However, such increases in localized productivity are unlikely to make up for the negative consequences of climate change on global agriculture, affected by the irregularity of weather patterns, more frequent droughts, sudden and violent floods, and the overall greater intensity of meteorological events.11 In addition to causing heat stress for crops, higher temperatures favor the proliferation of pests, alter soil geochemistry, and cause possible shocks to soil microbiotas that are crucial for the healthy growth of plants. Higher temperatures also can accelerate growth processes and increase irrigation water evaporation, to the detriment of plants’ health.
Food geographies are shifting globally, forcing production patterns and economies to adjust and reorganize themselves. As the interconnection between agriculture and climate change becomes clearer, new resilience, adaptation, and mitigation strategies are required that move away from the exclusive focus on increasing production. Offering a diverging path from the green revolution approach, which favored mechanization and intensive use of inputs (see chapter 5), emerging agroecological methods emphasize agrobiodiversity, synergies among different production sectors, composting and repurposing of materials, and a more efficient use of resources and inputs. They also incorporate local crops that farming communities around the world have developed over generations, as well as traditional technologies for soil management.
Crops that had been almost abandoned because of their low yields, high labor requirements, or scarce adaptability to industrial production methods are newly appreciated because of their resiliency, resistance to drought, and nutritional value. For example, the cultivation of fonio, a tiny grain originally from the Sahel area in sub-Saharan Africa, is expanding thanks both to the plant’s capacity to tolerate drought conditions and to its lack of gluten, which meets consumers’ evolving preferences in the Global North. In East Africa, farmers have reintroduced sorghum, millets, and various beans to counteract the failure of rains. In India, traditional rice varieties, green gram, and many pulses are being embraced as a response to water scarcity. The same is happening in Central America with amaranth.
Seed companies and biotech labs also are participating in the research on drought-tolerant crops, both through traditional selection processes and genetic modification. However, in the case of GMOs, the agribusiness’s ownership of the intellectual property of genetic materials limits farmers’ control over their crops because seeds from one year’s harvest legally can’t be set aside and used in the following growing seasons (see chapter 5).
Daring initiatives and new perspectives are necessary to address long-term sustainability in ways that take into consideration environmental, economic, and social issues while responding to consumers’ needs and preferences. Not only food producers but also all other stakeholders in the global food system have to be involved, including celebrity chefs. US chef Dan Barber, for instance, has suggested that farmers shouldn’t grow what consumers (including chefs) demand, but instead we should all consume what the farmers need to grow to maintain the fertility of their soil and the viability of farming as a productive activity. Italian chef Massimo Bottura has launched soup kitchens where famous chefs cook food that otherwise would go to waste to feed those in need. Brazilian chef Alex Atala has highlighted plants and animals from the Amazon to provide jobs to people from the area and support better environmental management. Senegalese chef Pierre Thiam promotes fonio around the world, opening markets for smallholders in the Sahel area.
Although consumers, activists, and producers certainly play a central role in ushering innovation in the food system, the intervention of institutions, governments, researchers, and policymakers—both at the national and international levels—is fundamental to tackle urgent global issues that no single stakeholder can address, such as climate change. Solutions have to be found at a systemic level that include changes in consumption patterns, waste prevention, infrastructure improvements, efficient management of renewable resources, sustainable practices in food production, and advanced ecological approaches. The relevance of scientists, engineers, and designers operating in these domains cannot be discounted. Although not a silver bullet, technology need not necessarily be considered the enemy of sustainability, a position often embraced by those who fight for a healthier, fairer, and more environmentally friendly food system. Everything depends on who sets the agenda and the priorities for research, who owns the resulting technology, who has access to it and how, and its uses. As we’ll discuss in the next chapter, if managed through democratic means and not used only to concentrate power and wealth in the hands of a few, technology can play a positive role. It can introduce innovation, support change, and offer viable solutions for urgent problems in the global food system.