Food waste: a changing landscape

Abstract

In 2024, we mark a remarkable milestone—60 years of the Institute of Food Science and Technology (IFST) and its vibrant community of food scientists. This celebration is not just a testament to the passage of time but a journey through the evolution of our field. From the trade of spices and new ingredients, the development of canning in the 1700s and the rapid expansion in our understanding of the underlying science in the 1800s, each era has contributed to making our food supplies safer, more convenient, healthier, consistent, and of a higher quality. The marvels of the 1900s brought mechanisation, automation, groundbreaking thermal technologies, year-round availability of food, and unprecedented advances in food security ¹. In times of scarcity, science extends shelf life and maximises nutrition with minimal input. In times of abundance, science transforms food landscapes into exciting, flavourful, and convenient experiences. Unfortunately, memories are short. The food industry – which contributes to nearly a third of all greenhouse gases (GHG) – is often villainised forgetting that techniques such as pasteurisation and ultra-high temperature (UHT) treatment mean that fewer people and children would have to deal with the negative effects of food-borne illnesses.² Moreover, we are now able to cater to a variety of diets, health conditions, and preferences. The flip side of this though, is that just like the food we produce, the landscape of our waste too has changed1, 2

Food waste has always been a part of human society and archaeologists have used our edible discards to paint pictures of what life looked like long ago, and more creatively, have analysed food waste to tell political and social stories like the political influence of Maize in pre-Hispanic Peru³. In many ways, food waste is as - if not more - complex than food production because it overlaps so many areas of study. It's context matters. It is cultural, religious, local, geographic (see figure 1), economic, sometimes deliberate, is inextricably linked to the whole supply chain and has different definitions (Routledge Handbook of Food Waste, 2020). For example, the Waste and Resources Action Program's (WRAP) definition of food waste differs slightly from the Food and Agriculture Organisation's (FAO) definition because it does not consider food that is redistributed or converted to animal feed as waste. Surplus food distribution reduces wastage but is generally not considered a long-term viable solution ⁴. There are also distinctions between inedible and edible food waste, and pre (also referred to as food loss on farms) and post-farm gate (waste from households, institutions) making methodologies and comparisons more challenging.

In 1977, USDA's report Food Waste: An Opportunity to Improve Resource Use⁵ recognised that technological advancements in production had outpaced how we managed the increasing quantities of waste being produced and that food waste was a looming problem and a missed economic opportunity. They noted then that food waste reporting was vague, contradictory, and undefined, a sentiment shared by WRAP almost 30 years later when they started to research and publish reliable food waste data in the UK in 2008⁶. In 1977, the USDA estimated that 137 million tons or 20% of food produced valued at USD 31 billion was wasted from institutions and households. In today's money, that value is USD 157 billion. By 2018, despite a 100+ m increase in population during that period, food waste was almost halved at 63 million tons worth USD 161 billion⁷. This says two things – food waste can be and has been reduced but despite this, the overall value has remained constant when accounting for inflation.

In the UK too, post farmgate food waste has decreased from 16m tons in 2008 to 9.5 m tons in 2018⁸. This has been the culmination of incremental, transdisciplinary scientific endeavours across the supply chain, starting at the farm, through engagement with producers to invest and upgrade their capabilities. Given the input costs, valorising any food waste therefore presents a huge economic opportunity.

Food scientists have devoted a lot of translational innovative thinking into finding second-lives for food by products – both inedible and edible. In the 1920s, a significant commercial success was achieved in the pectin industry by utilising discarded lime peels, and later citrus peels from the juicing industry⁹. Whey is a notable success as a cheese industry byproduct¹⁰.

As consumer preferences shifted towards lower fat content, the industry responded by incorporating starch. In response to today's preferences for reduced sugar, increased protein, and clean labels, ingredient and food companies are turning to unconventional sources like peels and misshapen fruits which still contain antioxidants, polyphenols, fibre, vitamins, minerals, proteins, and peptides. Extracting these components can contribute to enhancing our diets and provide excellent functional properties¹¹. As an example, the fine protein fraction from brewers spent grain can stabilise emulsions¹². Wheat bran, wheat germ, vital wheat gluten, are all ways to use cereal by-products (which are some of the most highly wasted crops pre-farm gate) in high-protein vegan foods. Some of these products even find uses in nonfood industries¹³. UPP is one company I met at a FoodHack event focused on alternative protein, aiming to utilise the 80% of the broccoli crop left on the field to extract protein. This simultaneously addresses the problem of pre-farm gate food waste (48% of which is out of the farmers control¹⁴), and sustainable protein production. Scientists across packaging, feed and flavour disciplines explore innovative applications for food waste. Vegetable and fruit waste, when fermented or used as substrates, not only enhances feed nutrition but also offers solutions in packaging for a more circular approach^{15, 16}. Some companies are using food waste to produce energy in food factories¹⁷, which is a novel response to the controversial use of biofuels.

Valorised ingredients incorporated for functional and fortification purposes can help alleviate wastage, but there is a newer emerging category of food in the eyes of the consumer – Value added surplus products (VASP) more commonly known as ‘upcycled food’¹⁸. However, is there demand? Up until recently, products that specifically marketed themselves as upcycled or using by-products/surplus were virtually absent on supermarket shelves. This is changing with companies like DASH using ‘wonky’, surplus, by-product fruit and vegetables. Consumer trends indicate that the demand for upcycled food will rise as consumers look to more familiar sources for nutrition that are at the same time minimally processed¹⁹. Consumers also prefer the word ‘upcycled’ to words like ‘reprocessed’²⁰. These products lie at the intersection of two consumer trends: sustainability and ‘clean labels’. Consumers seek sustainable products with added nutrition, but many upcycled items involve complex processing with unfamiliar technologies and aids. It becomes important to explore ways of communicating this without coming across as ‘ultra-processed’. It could be, that the key to the success of an upcycled product is to limit the on-pack text simply because consumers may not understand the full picture and are already grappling with huge quantities of information when they go shopping.

A study by Kerry revealed that consumers are more likely to embrace products that contribute to waste reduction. However, it prompts a reflection on whether consumers would willingly choose something actively marketed as being made from waste. Perhaps, Ogilvy could get them to but there is much more to purchasing choice and appeal than just sustainability or the unique selling point (USP) of utilising food waste and upcycled products therefore must be carefully positioned²¹ as with any other product launch. If this is misunderstood, it will only lead to more resources being used only to then end up as waste/surplus again. A circular economy of a different sort!

Looking at the sea of plastic waste from the food industry, it highlights just how important it is for companies to pay attention to their packaging. Many products still use packaging that is not widely recycled kerbside. The Extended Producer Responsibility despite delays in its implementation, is likely to induce change in this area as it still mandates reporting the data in 2024. If you’ve ever wondered why cucumbers in the UK are shrink wrapped because it seems like a waste of plastic, it is this very balance between controlling food waste and controlling plastic waste. That plastic wrap increases the shelf life of the cucumber by 3x. Most food packaging in the UK and elsewhere is plastic and multi-layered making it hard to recycle. Plastic is the least recycled material in the UK and 600k tonnes is exported every year. More waste is also being incinerated each year²³. One needs to therefore weight out the benefits of upcycling from a non-food waste generation point of view too. A key point in the marketing of upcycled foods is reassuring consumers on quality, environmental benefit²⁴ and communicating clearly and transparently²⁵. As such, if the product itself has an environmental benefit but the packaging is not kerbside recyclable, or not recyclable, then the dissonance might actually deter people from purchasing²⁶, considering that the consumer who is interested in buying an upcycled food cares about sustainability.

Another consideration for upcycling food is that of resource usage. WRAP estimates that between 0.9-3.5 million tonnes are wasted pre-farm gate²⁷ and it has to do with aesthetic standards, poor prices, and lack of human resource^{28, 29}. 25% of the fresh water used for agriculture is used to grow food that is never consumed and while upcycling can enhance nutrition, and reduce food waste, it does not tackle issues of food availability and food security which are systemic problems.

As the upcycled/VASP category becomes more popular, it is crucial for those in New Product Development (NPD) to collaborate internally and externally with those before and after them in the food supply chain to understand the effects of variability and safety, which is an inherent challenge within the category but is well-understood. Such seasonal variation is no stranger to the dairy industry for example. There are pages of research dedicated to the benefits of valorised or upcycled products, but it is only when scalable solutions are found, that these can be practically put to use.

Recognising which form of the upcycled / valorised food is most suitable for which application is also important. For instance, two contrasting case studies reveal that accommodating variability may be more feasible in a smoothie manufacturing operation as compared to an industrial ingredients’ supplier³⁰. In my experience with SMEs, they demonstrate unique agility and swift response capabilities, emphasising their significant potential in reducing food waste with the right financial support. In a recent engagement with a small ready-meals manufacturer, it became evident how easily they could integrate surplus vegetables into their operations. In the UK cider market for example, more than half of cider drinkers would like to see cider made from wonky apples³¹ so looking at trends within categories can also suggest which ones may be most accepting of an upcycled product to maximise product success.

Despite all the successes, it is still important to note that food waste is not just an unfortunate by-product and cannot be ‘fixed’ by a technological or organizational effort alone³².

The solutions seem obvious – produce less, embrace a little inconvenience, and be less spoilt for choice. As one study interviewing retailers in the UK highlighted - ‘with increased availability comes waste’³³. However, this is unlikely to happen so we must move our attention to an area of high impact in the food waste conversation, which remains un- and under-addressed. This is the t-rex in the room: household food waste. Many ‘behaviour influencing’ programs have brought this problem to the public's attention such as the ‘freegan’ movement in the west in the 90's, the ’love food hate waste’ campaigns, and social initiatives by chefs to boost the popularity of ‘ugly fruit’ and use all parts of the animal or vegetable.

Of the 10.7m tons of food waste in the UK, households contribute a whopping 60%. Considering only post-farmgate edible waste, the contribution rises to 70%³⁴. Unlike waste generated in factories, which can be repurposed as by-products or animal feed, distributed surplus from households or household food waste has limited options. It can be used for anaerobic digestion, composted, or landfilled, aligning with the food hierarchy mandated for most retailers and businesses. Many studies have challenged the food hierarchy, and perhaps they are right. What is needed is not a linear chain, but rather a multi-pronged approach where we do what's possible within the context of the size of the business or household³⁵ to avoid food waste from going into landfill.

During my visit to a waste-management service provider in August 2023, a noteworthy observation was that food waste stands out as the primary contaminant in general waste, making it unsuitable even for recovery as fuel. This highlights the need for waste segregation, a practice that, unfortunately, does not happen at a meaningful scale yet. Only half of the councils in England collect food waste separately at the moment, although this is going to change by 2026, and separate collections are increasing year on year^{36, 37}. In areas without centralised wet kitchen waste collection, innovative methods enable rapid composting at the household level^{38, 39}. However, challenges exist for those pressed for time, resources, or space. To address the primary source of food waste, households and councils should provide this infrastructure without imposing financial burdens on the individual. The implementation may also face challenges in large apartments and high rises but again, given that 77% of households in England & Wales live in houses/bungalows, and only 21% in apartments⁴⁰, it is more efficient to try and target the area of higher impact.

The capitalist system we are all a part of means that waste and mass consumption go hand in hand⁴⁰ so to solve the problem, efforts must involve the food sciences, social scientists, those who understand consumer psychology, the public, and policy makers. Public funding should concentrate on solutions for waste across the supply chain, engaging with universities and stakeholders through SME innovation consultancy or Knowledge Transfer Partnerships. There is precedence for how this collaborative approach can foster IP generation and take us closer to finding a solution for a pressing problem⁴¹. Research must find ways of being applied in a real-business context. The University of Nottingham has a considerable body of research in by-product valorisation and process development⁴² but also has a commercial arm (where I work) that uses this vast knowledge as a base for offering food & drink SME's technical support consultancy. This is just one example, and others do exist not the only example.

Secondly, and importantly, without overemphasising individual action over government-led systemic change, how individuals manage home waste could significantly impact landfills and GHG emissions from food waste. Changing behaviours and asking consumers to buy as much as they need is a long process, but until we get there, for those with the capacity, sustainability can be fostered at an individual or small-business level through simple yet impactful practices, such as composting⁴³. In this way, each small effort contributes to the larger narrative of responsible food waste management.