1. Introduction and Background Literature
Today, food-farming systems cause up to 270,000 km
2 of land/year to be deforested [
1] or desertified and are associated with approximately 1/3 of the world’s greenhouse gas emissions [
2]. In addition, recently, the United Nations revised its population estimates and now predicts that there will be approximately 11 billion people on the planet by 2100 [
3]. This sharp upward revision (previously the UN had estimated that global population would peak around the year 2050 at nine and a half billion) reignites discussions about global food security and poses the question: can the Earth provide for so many [
4]?
While much of the discussion on “how to sustainably feed 11 billion” focuses on boosting crop yields and increasing farm productivity [
5], a growing body of work proposes that reducing food waste is an effective strategy for improving global food security and reducing agriculture’s impact on the ecosystems of the planet [
6,
7,
8,
9,
10,
11,
12,
13,
14]. For instance, in their widely-cited paper on “solutions for a cultivated planet,” Foley et al. [
15] propose that reducing food waste, along with boosting production on underperforming lands and shifting diets towards less resource-intensive foods, could help double the amount of food available for human consumption while simultaneously protecting our planet’s natural environment. Thi et al. [
16] build on this argument by pointing out that reducing food waste in developing countries is a major opportunity to promote more sustainable development.
To contribute to this literature, our paper begins with the UN’s Food and Agricultural Organization’s 1981 definition that describes food waste as occurring when wholesome edible material intended for human consumption is discarded, lost, degraded or consumed by pests at any point in the food supply chain [
17]. Additionally, this paper moves beyond this description by building on the more recent literature that distinguishes between two different kinds of food waste [
9]. The first type is the loss of food during production and post-harvest processing and occurs mostly in the Global South. The second type is waste by consumers and retailers and is mostly an issue in the Global North.
While it is widely acknowledged that data on food waste are difficult to come by [
9], what estimates we do have suggests that approximately 30% of the annual global harvest is never consumed by human beings [
7]. One of the most-cited recent reports on food waste was published by the FAO in 2011 [
6]. This study presents a life-cycle assessment of the global food chain and confirms previous estimates that approximately 1.3 billion tonnes of food, or a third of total global production, is lost. This study also provides a reasonably detailed account of where food is wasted, demonstrating that there are political and economic dimensions influencing where and how food waste occurs. More particularly, scholars working on this topic note that more food is wasted per capita in the Global North than in the Global South (nota bene, the term “the Global North” refers to North America, Western Europe, Australia and New Zealand as well as the developed parts of East Asia. This term is also used to refer to the “Industrialized world”, the “Developed World”, or high-income countries as per the World Banks Classification—see the Methods section below. Similarly, the “Global South” is used for Africa, Latin America, and developing Asia, including the Middle East) with Europeans and North Americans wasting approximately 100 kg/capita of food each year. In Sub-Saharan Africa and South or Southeast Asia only 6–11 kg of food is wasted per person per year. Furthermore, the causes of food waste differ around the world. In the Global North, the low cost of food means that a tremendous amount of food spoils before being eaten or it is simply thrown out due to taste or cosmetic issues. In the Global South, however, the causes of food loss are mainly associated with inefficient harvesting, inadequate storage and cooling facilities, as well as poor quality packing and manufacturing processes. In other words, in the developing world, food loss happens at or around the farm gate, whereas in the developed world food loss occurs closer to the consumer end of the food chain [
9,
18].
There have been numerous attempts to estimate the value of these losses. For instance, Buzby and Hyman [
19] used USDA data to estimate that Americans wasted $165 billion worth of food in 2008. These authors further estimated that meat, poultry, and fish represented 41% of this loss; vegetables represented 17%; and dairy products represented 14%. This translates to 124 kg of food lost per capita, costing the average American $390 per year. In terms of the food waste in the Global South, Hodges et al. [
20] confirm that post-harvest losses typically occur at or around the farm in the least developed countries. Hodges et al. [
20] further argue that the best strategies to reduce these food losses include farmer education, better infrastructure to store food, better access to markets for small-scale farmers, and the creation of opportunities for collective marketing.
In summary, the literature on food waste demonstrates at least two overarching themes. First, since a huge proportion of food produced globally is wasted, reducing food waste represents a significant strategy to help reduce agriculture’s impact on the planet while address rising global food needs. Second, although socio-economic and technological causes of food waste are very important, they vary wildly between regions. The purpose of this paper, therefore, is to use quantitative methods to assess the relative importance of the various socio-economic factors that contribute to food waste in the Global South (aka the Developing World), as a way of identifying policies that may be more effective at addressing this serious global problem. Given the focus on food waste in low-income countries, the term food waste in the rest of the paper refers to on the losses that occur in and around the farm. Our analytic process involves a statistical approach to identify and weigh the importance of different socioeconomic and technological variables in determining food waste focusing on lower income countries. We then use these calculations to provide an initial estimate as to the potential effectiveness of different policy scenarios. This allows us insight into how to reduce food waste in already food-insecure regions of the world.
4. Discussion
Our analysis illustrates that the problem of food loss manifests itself differently in low-income and lower and upper middle income countries. Overall, the results presented here suggest that food loss should be addressable through policy. Our analysis shows technical fixes to the system, including improvement in machinery, roads, and telecommunications, made more of an impact in lower-income countries. Similar to Brooks et al. [
21], Fraser et al. [
22], and Thyberg et al. [
23], through empirical analysis we were able to identify a set of factors and their relative weight of impact on reducing food loss. These factors have also been identified by other researchers working on food waste in the developing world context.
As Thi et al. [
16] and Liu et al. [
35] note, in developing countries, and especially in tropical regions, there is a need for more investment in improved storage, transportation, and cooling infrastructure. There is also critical need for increasing producers’ access to food processing, packaging, and new markets beyond their local ones [
35]. A joint FAO and World Bank report suggests that technologies and practices, such as postharvest grain management, pest management, enhanced storage structures, as well as enabling policies and institutional arrangements for grain marketing, could significantly reduce food loss in Africa [
33]. For example, technologies such as small-scale rice dryers and threshers, plus new bagging techniques, which have been transferred from Asia to Africa, could make a significant difference in grain processing and storage. The spatial analyses presented above, therefore, should be seen as agreeing with these conclusions from the literature, and in particular, our results contribute to a rising consensus that Africa could particularly benefit from such technical solutions.
Technical solutions go along with an enabling environment, where government support or private sector investment in innovation (especially within “infant” industries) can be supported and encouraged. Botswana, for example, has the economic ability and the policy framework to encourage agricultural technology and innovation such as improved sorghum milling technology [
33,
36]. Coupled with high-tech innovations that require major public or private investment, simple, low-cost technology such as a “triple bagging” (also known as Purdue Improved Crop Storage (PICS), which is a relatively simple way of reducing post-harvest losses) has been shown to reduce food waste for cowpea and maize farmers across Sub-Saharan Africa [
37]. More specifically, hermetic (airtight) PICS bags provide long-term, reliable protection against many pests without the need for chemical pesticides. Thus, this system has proven to be economically beneficial in many food systems in Africa [
38,
39]. Such affordable technologies could make major contributions toward addressing food loss; as Abass et al. [
40] suggest, Tanzanian farmers’ poor knowledge and skills regarding post-harvest management remains a major contributing factor to food losses.
Poor quality road networks present another major issue for growers, wholesalers, and retailers of food. This is especially true for people who produce/sell perishable fruits and vegetables, as they suffer significant losses due to the lack of fast and dependable transportation infrastructure to move produce to markets. As Kader [
41] notes, the availability of horticultural products in most developing countries is significantly impacted by poor roads, the short supply of vehicles and other modes of transportation suited for fresh produce, all of which lead to inadequate transport of horticultural crops. For example, in Kano State, Nigeria, Olayemi et al. [
42] estimate loss during transportation to be about 26% for tomatoes, 15% for bell peppers, and 10% for hot peppers. Uneven roads and the use of lorries, bicycles, or buses for transport exacerbates loss because of mechanical damage to fresh tomatoes and peppers caused by strong vibrations and impacts [
42].
Communication along the food supply chain is also critical to ensure that producers know where demand is, and that retailers can adequately source and plan. Thus, addressing food loss will also entail investing in the technology necessary to transmit timely information about price trends for agricultural products in local, regional, and international markets [
43]. In Honduras, for example, low-cost information and communication technology (ICT) solutions, such as SMS or text messages, have been found effective for disseminating price information to a significant portion of the Honduran population, thanks to the nation’s broad cellular telephone coverage [
43]. Disseminating prices over the radio presents another low-cost solution, although it is not as effective as cellular phone messages [
43].
It is important to set this discussion on these local against a more global backdrop. In particular, we must recognize that that as countries achieve the efficiencies discussed above in dealing with farm-gate and postharvest losses in their food systems through technological fixes, they may not see overall reduction in food waste. This is because as countries grow rich enough to invest in this kind of infrastructure, the problem of food waste may shift away from the farm-gate and manifest itself as the kind of waste caused by consumers and retailers in the developed world. Here, it is important to reflect on the results of our statistical models that GDP is positively related to food waste. In middle-income countries, such as South Africa, although food waste from agricultural production, post-harvest handling and storage, and processing and distribution sill make up the bulk of losses along the supply chain, increasingly consumer food waste is being noted as a major problem [
44,
45,
46]. Households often tend to prepare/buy too much food, especially staples such as porridge and rice, which ends up thrown away, along with expired or spoiling bread. Although the lack of proper meal planning and education around preventing food waste are major issues, marketing strategies by food retailers, such as promotional specials that are intended to clear out food items before they reach their sell-by date, has been noted to contribute to food wastage at the household level [
44].
Similarly, in China, technological and infrastructural development in past decades have greatly reduced postharvest food losses; however, consumer food waste has grown due to increasing affluence and rapid urbanization [
35,
47]. Lui et al.’s review of food loss and waste in China estimates the food loss rate of grains in the entire supply chain to be 19.0% ± 5.8% Meanwhile, consumers are wasting 7.3% ± 4.8% [
33]. It has even been estimated that food waste now constitutes 37%–62% of municipal solid waste in some Chinese cities, with catering services and restaurants accounting for a major portion of this [
47,
48]. For example, in Hangzhou, daily food waste production from catering services was about 1184.5 tonnes in 2010 [
48]. Growing disposable income amongst contemporary Chinese seems to be eroding the traditional virtue of “cherishing food” as people now buy more food than necessary and order too much when they host guests in order to show their hospitality and wealth [
35]. Given that consumers in China are responsible for a large portion of waste, awareness-raising campaigns, which have significantly increased recently in the mainstream media in China [
35], could potentially redress the food waste problem. There is no doubt, however, that changing the way that people relate to their food, including shopping habits, consumption patterns, and what is thrown out, is a major challenge, but communication campaigns could influence consumer behavior and initiate change [
8].
5. Conclusions
This paper began by reviewing research that shows approximately one third of the world’s food is lost and demonstrated that the causes of this lost vary between the Global North (where food waste happens predominantly at the consumer and retail end of the food chain), and the Global South (where food waste is mostly a function of poor storage and marketing infrastructure). To explore this issue in more detail, we focused on the socio-economic determinants of food loss in lower, lower-middle, and middle-income countries and revealed that although GDP is positively related to food loss, investing in agricultural technologies, the transportation infrastructure and communications technologies can help reduce food loss. Overall, the results of our statistical modelling suggest that as much as 49% of this food loss could be eliminated by improvements in these factors. However, it is also important to note that food loss can also be influenced by many other factors such as access to regular energy supply, government policies and regulation and many others. Therefore, it is important to recognize the various drivers of food loss in detail and as location specific as possible. This study only provides a few determinants out of many. Such studies, supplemented with more location-specific in-depth studies, would greatly help to refine our understanding of the different drivers of food loss. In addition, we also note that as these farm-gates and marketing problems are addressed, overall food loss may not decrease. This is because as countries grow wealthy, they shift from farm-gate “food losses” to consumer and retail “food waste”. As a result, while reducing food losses may be amenable to investments in infrastructure, the shift to food waste calls for more of a sociological fix than a technological one.