Table of Contents
Introduction
The wastage of food is one of the major problems facing the world today. The problem is particularly concerning when it is considered that there are regions of the world where there are shortages of food. Current food systems are not any close to efficient. Estimates show that about a third to a half of food produced today is lost somewhere between the point of production and consumers (Tscharntke, 2012, p. 3). The food wastage occurs mainly in developed countries. The concern is not just that there are shortages of food in the third world, as well as incidences of famine, but also that within the developed countries in which food is wasted there are low-income citizens who sometimes go hungry because they cannot afford it. There are expectations that international organizations concerned with food, as well as governments, will create more legislation, campaigns, and initiatives in order to address the issue of wastage.
Nevertheless, there needs to be a proper management strategy if the objective of reducing food waste is to be achieved. It is obvious that food wastage cannot be eliminated completely, as it is inevitable that there will always be some food wasted. Moreover, there are parts of food that are not edible, and people will always have to dispose of those parts, with bits of consumable food alongside. Hence, there is a need for food waste management approaches, of which there are numerous. The problem of food waste is solvable if waste food management is more focused on the supply chain, which would be a more sustainable approach.
It is important that research does not just aim to find solutions food the management of food waste, but also addressed the three aforementioned. This paper aims propose solutions for food management that takes into account social, economic and environmental ramifications, having experienced the scale of the problem in Chippewa Valley Farms, and hence the need to find viable solutions. The first section of the paper introduces the subject. The second section defines food waste, as well as classifies them. The third section presents and discusses the available food waste management alternatives using a food waste hierarchy developed from classification in the section second. The fourth section concludes the paper.
Definition and Classification of Food Waste
The first step toward food waste management is to properly define the exact meaning of the phrase, ‘food waste’. Regrettably, there is no consensus as to what should be the correct definition of the term (Garcia-Garcia et al., 2015, p. 66). This paper will work with the definition of waste food as food and drink materials that are intended for ingestion by humans but fails to serve that purpose, in effect ending up elsewhere. The definition will also encapsulate parts of food that are not edible, and therefore end up being disposed of wherever. The inclusion is informed by the fact that when these inedible parts are disposed of, bits of edible parts tend to be disposed of alongside them.
The identification of the most effective approach to the management of food waste depends significantly on categorization. Categorization is necessary for employed management approaches to achieve optimal economic and social benefit. This is because different types of food require different treatment methodologies and that each type needs to be linked with a methodology that would be most effective for it. Only when the classification is done properly would a sustainable solution that takes into account social, economic and environmental ramifications be achieved. These categorizations are assessed, and a discussion of the usefulness of each classification to the optimization of food waste management is presented.
Garcia – Garcia et al. (2015, p. 69) explained nine indicators that can be used to classify food in such a manner as to aid sustainable food waste management. If these indicators are used, characteristics emerge that provide a systematic categorization of various types of food waste that make it possible to choose amongst the available alternatives for waste management. It facilitates schemes that prioritize decisions on sustainability in terms of the three anchors of sustainability: (1) social considerations, which can be implemented either negatively, for example by through taxation, or positively, for example through the redistribution of food to people who need it; (2) economic effects, which can either be negative, for example the economic cost of food waste disposal, or positively, for example the economic benefit derived from proper food waste management; and, (3) environmental ramifications, which are in most cases negative, for example the emission of greenhouse gases, but can be positive as well, for example, food waste can be used to rid waste water of pollutants. The indicators are discussed here.
One indicator is edibility, in which case food waste is considered edible if there is a point in its life cycle when it could be eaten by humans. Otherwise, it is described as inedible. Some of the food products that are considered inedible include bones, scales, vegetable stalks, animal and fruit skins, and fish intestines, among others. Food products that are considered to be biologically edible but lack demand also fall under the category of inedible products, as they cannot be reallocated for consumption by humans. It follows that the edibility of food waste is a function of both time and space or geographical area. Types of food that are sold/bought together with their inedible parts, for example, fruits and their skins, are considered edible.
Another indicator is state, a characteristic that assesses only the edible food products, and takes the form of either eatable or uneatable. A food product is eatable if, at the time of its management as food waste, it still has properties that make is fit for consumption by humans. Otherwise, the state of a food product is described as uneatable. Food products need further processing to be fit for the market or human consumption are considered to be in the eatable and unprocessed state. Food products can go from being eatable to being uneatable if they are damaged by activities along with their supply chain, for example overcooking during manufacture, spillage or spoilage during distribution, or expiry at the time they reach potential consumers. Food products that contain both eatable and uneatable parts are managed wholly as uneatable.
A third indicator is origin. Food products that are produced by animals, or are parts of animals, are described as being animal-based products. These include fish, dairy products, pork, honey, chicken wings, eggs etc. food that is produced by plants, or are parts of plants, are described as plant-based. Food products that are both plant-based and animal-based are described as either of which ingredient is predominant. If the predominant ingredient is plant-based, the food product is classified as plant-based. Otherwise, it is classified as animal based.
The complexity indicator characterizes plant-based food products as either single or mixed. Single food products are made up of only one type of plant ingredient and do not contain any other ingredient, whether an animal-based ingredient or plant-based ingredient. The food product must not have gotten in contact with other food products or materials. Food products are described as mixed if they contain more than one plant-based ingredient, and do not contain any animal-based ingredients.
A fifth indicator is the presence of animal-based products in food products. If the food product is animal-based, it is classified as meat. Animal-based products include fish, animal products, which in this case means products produced by animals, or, animal by-products, which in this case means parts of animals used for food that are not intended for consumption by humans, for example, animal skins, horns, fish intestines etc. When the food product is not based on plants and is mixed, it is as assessed on the basis of the whether it contains materials based on animals, or has made contact with animal-based materials.
The sixth indicator is treatment, which considers whether food is processed or unprocessed. Food is considered processed if there is no need for further processing. In other words, the processed food is fit for human consumption as it is. Foods like fresh fruits and vegetables fall into the category of processed food products. If at the point of its management as food waste a food product needs treatment to be fit for human consumption, then it is considered to be unprocessed. It follows that any eatable or edible food products are assessed at the treatment indicator stage.
The seventh indicator is packaging. A food product is considered to be unpackaged if it is not contained in a packaging material. Food product is also considered to be unpackaged if it is actually packaged but there is no readily available technology to unpack it. In the absence of the two aforementioned cases, food is considered to be packaged. Packaging as an indicator is important because the type of packaging, if present, will inform the choice of food waste management alternative.
The eighth indicator is the biodegradability of the packaging material used and applies to packaged food products. Biodegradability is this case means that the material out of which the packaging is made can be broken down and digested by bacteria and/or other micro-organisms. Assessment of biodegradability entails authenticating whether the material used for packaging has been certified by the relevant authorities as compostable or anaerobically digestible. Typically, paper, bio-plastics, or any package materials that are based on plant products constitute biodegradable packaging. Generally, packaging materials made of glass, plastic or metal constitute non-biodegradable packaging.
The last indicator is the stage of the food product in the supply chain. The stage of the supply chain indicator characterizes food as either catering food waste or non-catering food waste. Catering food waste covers waste from hotels, hospitals, restaurants, and schools, among other food services, as well as food waste from households. Non-catering food waste is that that is generated along the supply chain in the early stages, which could be during manufacturing, during farming, during distribution, or during wholesaling.
Food Waste Control and Management Options
The selection of the most effective food waste management alternative starts with assessing the discussion of the nine stages, and the determination of nine food product characteristics. The hypothesis is that a combination of nine indicators is associated with a favorable waste management solution, accounting for regulations and social, environmental and economic ramifications. This section provides a number of food waste management alternatives for the various types of food waste identified using the nine indicators discussed in the earlier section. In order to select the most effective food waste management alternative, a food waste hierarchy needs to be developed, as it is an instrumental tool for classifying the various options of food waste management, on the basis of sustainability and results.
We can do it today.
As to what the order of the available options in the hierarchy in question should be, it is a subject of debate. Different people would prefer some alternatives to others, for example, anaerobic digestion may be prioritized over composting. The ultimate objective, however, is to prioritize those options that promise better social, economic and environmental outcomes. Hence, there are a number of slight variations of food waste hierarchies. One food waste hierarchy adopted by Garcia-Garcia et al. (2015) is shown in the figure below.
The application of food waste hierarchy to food products is a daunting task, owing to the fact that at each stage of the supply chain, there are different numbers of actors, which causes the wastage of food, as well as because food products are so heterogeneous. This makes it necessary that the food waste hierarchy is assessed in terms of the type of food waste, rather than considering all food waste as such and treating as a whole. The application of food waste hierarchy, therefore, needs to be on a case by case basis, as pertains to the type of food waste.
If a business or farm produces both animal-based and plant-based food products, food waste management should involve collecting them and treating them separately, as well as assessing them differently. However, if food products are such that the resultant waste is undifferentiated food waste made up of both animal products and plant products, food waste management should consider them as a whole, and the waste is classified as a mixed product. It is clear that separate collection of food waste has the benefit of enabling targeted management approaches that can be executed on different streams of food waste. Where food waste cannot be collected separately, it is recommended that it be sorted as thoroughly as possible, although some alternatives for management would not be available in some of such cases, for example, food wastes based on plants but have made contact with animal-based products cannot be fed to animals.
It is difficult to develop a classification that covers every type of food wastes, as there are too many types of wastes, as well as the fact that food waste are widely inhomogeneous. Another reason is that there are many management alternatives because there are several physical and chemical avenues for extracting biological compounds from a food product, as well as several possibilities to utilize various types of food waste for application in industries, such as the treatment of wastewater of pollutants. Therefore, it is not feasible to take into account all the options explicitly for all the classes of food waste. This makes it necessary to carry out a study specifically targeted at each type of food. This would provide an opportunity to extract biological compounds that would be applicable to industrial use, prior to considering options that are ranked lower in the hierarchy of waste food.
Land-spreading can be utilized with most of the types of food waste, but, in consideration of the food waste hierarchy shown in the figure, there is less benefit associated with this alternative than composting. Both waste food management alternatives can be applied to the similar types of food waste. This paper has considered composting only, as both it and land-spreading treat the same type of waste of food. Land-filling is left out because it has a significant impact on the environment, as well as negative social and economic ramifications. Some of the most sustainable food waste management alternatives are discussed below.
Consumption by other humans
Redistribution of food that would otherwise be considered waste in certain geographical regions, or by certain groups of people of a particular geographical socioeconomic class, is considered to be the optimal alternative for food waste management. The particular food products valid for redistribution are those that are processed, edible, and eatable, as was discussed earlier in the paper in the section pertaining to food product indicators. It is worth noting that the term ‘processed’ as used in this regard does not necessarily imply that the final food product was processed fully according to the initial plans of the food business. For instance, a surplus of potatoes that were initially meant for use to prepare crisps may be distributed in their raw form, for example, unpeeled, if they have been assessed and found to be fit for consumption by humans.
Food products that can be redistributed tend to be in plenty in the developed world. That happens for two main reasons. One reason is that people in those regions tend to be so well off that they buy a too much food, and consume only a small portion of it. They dispose of the rest, even when it is still fit for human consumption. Another reason is that retail stores tend to focus on the aesthetic look of fruits, vegetables, fish and other similar products. Food that does not look beautiful to consumers, who do not buy them for that reason, tend to be disposed of, just because of their lack of aesthetic (Neff, Spiker, & Truant, 2015, p. 12). These consumable food products can be collected and redistributed to people who need them, which includes people in the third world, as well as people in the first world who cannot afford food. Redistribution can be carried out by charities, NGO’s, and government organizations, or via food banks.
Feeding to Animals
There are instances when food products are not healthy for consumption by humans but are suitable for animals. It is in these cases that food products that are considered waste from the perspective of humans are fed to animals. In other words, in order to be fed to animals, the food products must not just be fit for animals, but it must also be uneatable for humans. If food products that are eatable to humans are fed to animals, then it is considered food wastage if there are humans who need it. The food products fed to animals must also not be packaged, or if packaged, the packaging must be readily separable from the food product. The food product should also be a non-catering waste. Plant-based single food products that are inedible non-catering waste can be feed to animals depending on the type of food waste. In this case, food products must be assessed independently for each type of food waste.
If the food product is mixed, it is only fed to animals if it does not contain meat, as well as if it has not made contact with animal-based products, or by-products. Mixed food waste from manufacturers that contain animal products should be fed to animals if the main ingredient is not an animal product. Meat or products based on plants but contain meat as well should not be fed to animals. Eggs and products derived from or containing eggs as ingredients should not only be fed to animals if they come from manufacturing or agricultural stage and should be subjected to particular treatment. Milk and dairy products should be fed to animals only if they are processed in a manner similar to that required for human consumption, or unprocessed if the firm concerned is certified as an establishment for milk processing.
Anaerobic Digestion
Anaerobic digestion refers to the process by which microbes decompose organic matter into inorganic nutrients, carbon dioxide, methane and compost in an environment that is depleted of oxygen but has hydrogen gas (Ljupka, 2010, p. 9). All food products are organic matter, and, therefore, anaerobic digestion can be applied to food waste. However, the food wastes need to be unpackaged, which means that it should not be contained in any packaging, and, if packaged, the packing should be separated from the food waste. If the packaging is biodegradable, then the food waste packaged as such need not necessarily be separated. Anaerobic digestion is superior to land-filling (Ljupka, 2010, p. 72).
Although anaerobic decomposition is effective, its application in the diversion of organics from land-fill has a couple of problems. The first problem is that of cost. Modern Anaerobic Decomposition plants are cost up to $600 per annual ton capacity (Ljupka, 2010, p. 73). The cost of operation of anaerobic decomposition plants is also substantially high. The operational costs range of $100-150 per ton of waste delivered at the plant which is comparable to the gate fees at Waste-to-Energy plants and much higher than the average landfill gate fee in the U.S. of $42 per ton (Ljupka, 2010, p. 73). However, the costs have to be considered in relation to the social and environmental cost of alternatives like land-filling. In that case, anaerobic decomposition is considered a preferable food waste management alternative to land-filling.
Composting
Composting refers to the decomposition of waste food and other organic materials into soil that is rich in humus. Such soil is commonly known as compost. Most food waste can be converted into rich compost. Some of the types of food waste that can be composted include meat, eggshells, coffee filters, bread, grains, dairy products, vegetables, and fruits. If anything is produced in a garden and/or can be eaten, then, generally speaking, it can be composted. It is also necessary that food waste that is subjected to composition is unpackaged. This is because the packages may not decompose. Some of the packaging that may discourage this food waste management alternative includes foil, plastic, glass, condiment, polystyrene, and bottles. It worth recalling that food is described as packaged if either the packing is non-biodegradable, and cannot be readily separated from the food using available technology. Waste food types like bones, scales and red meat require a properly controlled food composting in order to avoid partial decomposition, as well as to prevent infestation by insects, pests, and vermin.
Composting leads to the production of biogas, among other gases. Biogas can be used for the production of energy. The energy is recovered through the direct combustion of the gas, and can be used to for cooking and heating, as fuel for vehicles, or to generate electricity. If used to power vehicles, biogas needs to be upgraded, and liquefied or compressed before being distributed. The recovery of energy generated from decomposition helps to address the issue of global warming and greenhouse gas emissions, in the sense that fuel that would have resulted in the deepening of carbon footprint is instead replaced waste food. This food waste management alternative has positive social and economic impacts. It also has a positive environmental impact. The combustion of recovered biogas is not significant in relation to global warming as the CO2 emissions are of biogenic origin, and thus GWP neutral, and the CH4 and N2O emissions are low (Bernstad, & la Cour Jansen, 2012, p. 2446).
Composting has several other advantages. Compost can be used as fertilizer. It preserves soil and water if viewed in relation to other alternatives. It avoids the production of methane and its release into the atmosphere, which is associated with the use of landfills. Compost also suppresses some plant parasites and diseases, as well as kills seeds from which weeds otherwise grow. It also restores the structure of soil after its damage by the use of fertilizers. It can contribute economically to people who produce it and sell it, thus improving their socioeconomic life. Industries that employ this food waste management alternative cut down on the cost of solid food waste disposal, can market their establishment as environmentally friendly, and complete the food cycle via returning the compost for agricultural use.
Thermal Treatment with the Recovery of Energy
The treatment of food waste with thermal recovery includes gasification, pyrolysis, and incineration. The main difference between the three is the temperature reached, which ranges between 400ºC and 1200°C, and the products generated, which include coke in the solid phase, char, slag and ash; carbon monoxide, carbon dioxide, nitrogen oxides, water, hydrogen, methane, and other gaseous hydrocarbons (Garcia-Garcia et al., 2015, p. 68). Although the application of thermal treatment of food waste to energy production is less efficient compared to the use of coal, in addition to the downside that it releases ash and other dangerous pollutants into the atmosphere, it is a good replacement of fossil fuels, and, as such, food wastes are considered renewable sources of energy.
It is also important to contrast the method with land-spreading. Land-spreading is the process of covering or coating the soil with food waste (Garcia-Garcia et al., 2015, p. 68). While land-spreading can create agricultural benefits, for example by enriching the biological, physical and chemical characteristic of the soil on which waste food is disposed, thus enabling crops to grow healthily, the nature of the coated soil needs to be suitable. According to Garcia-Garcia et al. (2015, p.68), this means that the amount of sand, silt and clay, organic matter content, depth and underlying geological parent material must be tested in the soil before deciding the convenience of land-spreading. The assessment of soil for such can be time-consuming, as well as too costly when compared to other food waste management alternatives.
It follows that thermal treatment is preferable, but only when the energy produced by the approach is recovered. The only advantage of food waste disposal by thermal treatment with thermal recovery is that is that it reduces the quantity of waste (Garcia-Garcia, 2015, p. 68). However, the energy that would have otherwise been put to other uses is lost in the form of heat, and ash and greenhouse gases are released into the atmosphere, as result contributing to global warming. In this case, land-filling is preferable.
Conclusion
The wastage of food is a major global problem. The problem goes beyond just the fact that food is wasted in some regions of the world, while there are instances of a shortage of food in other regions, as well as among certain populations in the developed world. An immediate solution is to redistribute edible and eatable food products to people who need them. In cases where food waste is unfit for human consumption, or redistribution is not feasible, it is inevitable that the food products have to be wasted.
Products that inevitably become waste need to be managed appropriately. Otherwise, there is a prospect of more problems arising. The problems often manifest in terms of social, environmental and economic ramifications. It is the need to avoid negative impacts in the three aforementioned respects that necessitate analyzing and making an informed choice of food waste management alternative. In order to accomplish this, food wastes need to be categorized properly, and each category needs to be matched with the right food waste management practice. The paper’s analysis indicates that better results are possible if the approach is taken.
A hierarchy was developed to address sustainable food waste management. The downside of the hierarchy is that the management alternatives at its top apply to fewer types of food wastes than the alternatives at the bottom of the hierarchy. As a consequence, there is a need for a wide range of solutions for treatment that is tailored for each type of food waste. For example, there has been a reduction in the previous overuse of animal feeding as a food waste management alternative, and this has partly been due to the acknowledgement of other alternatives, as well as due to legislation.
It is a complex and daunting task to evaluate the advantages of food waste management alternatives. It is hard to assess the factors that determine the convenience of solutions, as well as difficult to identify them. Some of these factors include the proximity of food waste to facilities that are used for management, the extent of demand for the by-products of food waste, government regulations, among others. Consequently, the food waste hierarchy should apply to each type of food waste as identified independently, rather than food waste in general. The analysis developed in the paper provides the concerned with information for comparing alternatives and choosing the one that has less negative impacts on the society, economy and the environment.
We can do it today.
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