In the UK around 15 million tonnes of food is wasted annually, equivalent to around a third of that purchased. Of the 7 million tonnes of household food waste generated in 2012, approximately 60% was considered ‘avoidable’ by WRAP, the organisation that produces authoritative statistics on UK food waste. Binned leftovers were the second largest contributor to avoidable household food waste, after food items that are ‘never prepared’ or ‘not used in time’. That 1.3 million tonnes of wasted leftovers costs an average household £141 a year, and accounts for greenhouse gas emissions equivalent to those associated with 7.5% of cars on UK roads (WRAP, 2013).
Stages in the process of becoming waste
One of the main reasons cited as to why we throw away good food is that we cook or prepare too much. Here, ‘leftovers’ and ‘food waste’ are often conflated. The discussion on reducing food waste then suffers from analytical over-simplification. Of course, it is not inevitable that leftovers will go on to become waste. Disentangling these terms allows for a clear articulation of the sequence of stages that food follows en route to becoming waste. The Sustainable Consumption Institute conducted a ‘food diary’ survey of around 2800 households to explore the relationships between the organisation of meal occasions, the production of leftovers, and waste generation.
To be explicit about these stages, first food is prepared for a meal. When ‘too much’ food is prepared for a meal, leftovers are generated. While some leftovers may be binned immediately, others may be placed in the fridge or freezer for (potential) later consumption. The refrigerated or frozen leftovers are then either eaten, saving leftovers from becoming waste, or binned and thus becoming waste. So leftovers are not problematic per se; it is wasted leftovers that are to be avoided.
In our research we took a two-stage approach – first, focusing on the flow of food to leftovers and exploring the factors that encourage the generation of leftovers at mealtimes and, second, on the flow of leftovers to waste and the factors that lead to their binning. Separating the stages enables a better understanding of the processes through which food waste is generated (Southerton & Yates, 2014).
Individual ‘choice’ and the temporal rhythm of eating
In a bid to reduce leftovers and thus household food waste, campaigns encourage individual consumers to stop and think before preparing food and take portion caution. Overemphasis on the action of individuals fails to appreciate the ways in which social, material, economic, and cultural factors shape and constrain the performance of eating and food-related practices (see Focus, this issue). While individuals may be said to choose the ways in which they consume, patterns of eating are clearly socially ordered and temporal rhythms are a hugely important aspect of this (Southerton et al., 2012). The temporal rhythm of eating dictates that individuals make similar ‘choices’ about eating at more-or-less identical times: quick, rudimentary breakfasts, a quick and simple lunch, and dinner in the evening comprising more complex and substantial dishes eaten with household members (Yates and Warde, 2015). The food we eat is largely the consequence of cultural conventions that have become embedded as habits and routines in daily life. In our research we take a ‘theories of practice’ approach and refocus the enquiry into food waste on the practice of eating, or the situated meal occasion, and seek to understand the characteristics of the meal occasion which encourage the generation of leftovers and subsequent binning of those leftovers.
Dimensions of temporality and leftovers
In line with our focus on the situated meal occasion research respondents completed a ‘food diary’ on a weekday and a second one at the weekend, recording a range of information about each meal prepared and eaten in the home that day. 2,784 respondents filled in 5,568 diaries, recording 10,872 meals. For each of these meals respondents reported the day of the week, the time and duration of the meal, with whom the meal was eaten, where the food or ingredients were from, how ingredients were stored, method of preparation, and who prepared the meal. Crucially, we also know how much was left over and what happened to those leftovers.
In our analysis, we first examined the factors surrounding the meal occasion that encouraged the generation of leftovers. Our results indicated that over-provisioning at mealtimes could be understood as temporally patterned. Fine (1990) identifies five interrelated dimensions of temporality: duration relates to the amount of time that is spent on an activity; tempo relates to the pace of the activity or characterises the speed of an activity; periodicity of activity relates to the frequency of its recurrence and regular intervals; sequence relates to the timing and order of the activity; finally, synchronisation entails the coordination of not only people but also practices. These five dimensions of time can be readily identified and are instructive in understanding the generation of leftovers from meal occasions.
First, let’s look at the periodicity of meal occasions and leftovers. Irrespective of day of the week, morning meals are the least likely to produce leftovers, followed by meals in the afternoon, while leftover food is most likely from the evening meal. However, the proportion of afternoon meals with leftovers varies considerably by day of the week. 27% of Sunday lunches are over-provisioned, which is more than 2.5 times greater than lunches on Saturday (10%) and four times greater than weekday afternoon meals (7%).
The duration of time spent eating and potentially the tempo are related to over-provisioning at shared meals. When looking at meals shared with others, quick meals (taking less than 10 minutes) are the least likely to be over-provisioned and even a small increase in the amount of time spent eating a meal (10 – 19 minutes) is associated with an increased likeliness of leaving food at the end of the meal. More prolonged mealtimes are much more likely to lead to leftovers. Meals with others that are more drawn out, lasting an hour or longer, are more than six times as likely to have food that is surplus to immediate requirements.
Tempo and duration in food preparation are also instructive in the production of leftovers. Meals containing ‘ready to eat’ and ‘quick-cook’ foods are less likely to result in leftovers; meals containing produce that can be eaten raw (e.g. salads and fruits), foods where preparation time has been outsourced (e.g. pre-packaged, convenience food), or food requiring minimal preparation (e.g. toast) are less likely to be over provisioned. Meals which require more complex (and time-consuming) methods, such as using the hob and the oven, are more likely to lead to leftovers.
In understanding why this might be the case, it is worth considering the sequential order of portioning and preparation of food. Foods that are (near) ready to eat can be more readily portioned on serving, reducing the likelihood of over-provisioning and therefore leftovers. On the other hand, foods requiring more involved preparation methods such as a joint of meat or a lasagne are likely to require portioning after preparation or, like rice and pasta, may change volume during the cooking process, making it more challenging to anticipate the amount of food prepared.
If understanding the generation of leftovers is complex, by contrast, the subsequent flow of leftovers to waste is a very simple process; it is explained almost exclusively by how much food is left over at the meal occasion. In short, the less food there is left over, the more likely it is to be thrown away. Leftovers are not problematic per se; it is seemingly insignificant amounts of leftovers – plate scrapings – which are most likely to enter the waste stream, that are to be avoided.
The analysis of our survey shows how a ‘temporal lens’ helps us understand the complex process through which food in the kitchen becomes waste in the bin. The analysis shows how the social significance of meal occasions is an important factor in encouraging the generation of leftovers. Meals that are simple to prepare, eaten quickly, and eaten alone are less likely to result in leftovers; by comparison, when more time is spent preparing and eating meals, and the meal is shared with others, the more likely they are to result in leftovers. This doesn’t mean we should recommend eating microwave meals alone in the name of sustainability. But it does show how questions of sustainability have to be understood in the context of the competing imperatives and conventions of everyday life, like eating ‘proper’ (healthy) meals, and eating as a family.
Evans, D. 2014. Food Waste: Home Consumption, Material Culture and Everyday Life. Bloomsbury Academic.
Quested, T. E., Marsh, E., Stunell, D. & Parry, A. D. 2013. Spaghetti soup: The complex world of food waste behaviours. Resources, Conservation and Recycling, 79, 43-51.
Southerton, D. & Yates, L. (2014) ‘Exploring Food Waste Through the Lens of Social Practice Theories: some reflections on eating as a compound practice’, in Ekstrom, K. (ed.) Waste Management and Sustainable Consumption: The Problem of Post-Consumer Waste, London: Routledge.
Yates, L. & Warde, A. 2015. The evolving content of meals in Great Britain: Results of a survey in 2012 in comparison with the 1950s. Appetite, 84, 299-308.
Jennifer Whillans is a Research Associate at the Sustainable Consumption Institute at the University of Manchester. Her research interests are in time use and the temporal organisation of people and practices in daily life.