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Wayne Martindale, Mark Swainson, Tom Hollands and Richard Marshall discuss the need to combine healthy choices with reducing carbon footprint in the convenience foods sector.

The sustainability of convenience foods

Balancing a national diet has provided public health agencies with many difficult choices and despite dramatic improvements in what we eat, consumers routinely demand more effective action to improve diets. So what is going wrong? The impact of dietary improvement is clearly not going far enough. This article identifies where more incisive actions can deliver positive health and sustainability outcomes. Popular convenience foods are typically targeted by media stories and consumer outcry; solutions will only be found through innovative development of healthier choices. The IFST’s recent ‘Food System Framework – a focus on food sustainability’ provides impetus for this to happen; it recognises that achieving health and sustainability while delivering accessibility, affordability and assurance is always going to be a tough call[1]. However, the food industry now has over 30 years of sustainability legacy to apply and such a platform provides an opportunity to rank sustainability requirements so that they keep step with those of consumers for positive health outcomes. This will result in actions becoming embedded into not just global but regional and national food supply chains. Our most popular and convenient food products deserve greater attention and the sandwich food category, a £3.5bn gross value-added industry, which crosses the meal, lunch and snack boundaries, is the focus of this article.

There is an urgent requirement for information demonstrating efficient food utilisation, provided in a format that resonates with all food manufacturers.

Reducing overconsumption

Figure 1 Training food professionals in sustainability is essential; more important is that this sustainability know-how is part of a curriculum for all stages of food supply so that technologists, developers and engineers are conversant with building
sustainability into food products.

Case studies of innovative product development can stimulate changes in the convenience food category, where there are very clear high-level calls to lower the calorific content of meals, lunches and snacks. Sandwiches are a good example of a convenience food for which there are moves to change how consumers eat or portion foods during meal occasions. Health and increasingly sustainability are being built into business strategies and the industry has already responded to regulator calls for improved nutrition over the past two decades[2]. This has been against a background of regulatory change and the deployment of techniques, such as nutrient profiling, which have revolutionised lowering the salt and sugar content of foods. The problem of overconsumption of these nutrients remains despite all of this and it is time to consider how efforts to reduce consumption can be extended to address the financial and social responsibility risks. These are often difficult to quantify but they are a significant part of health budgets associated with treating the non-communicable disease outcomes of an unbalanced national diet[3].

There is an urgent requirement for information demonstrating efficient food utilisation, provided in a format that resonates with all food manufacturers. In some cases, this information is now openly accessible for application in New Product Development (NPD) processes. An example is provided by the Global Access to Nutrition Index that ranks the 22 largest food companies on contributions to tackling obesity and undernutrition. Accessibility to this ranking data can be transformative for SME manufacturers, which make up over 90% of the industry, because it will guide sustainability reporting in food service, retailer or consumer relationships, where there may currently be none. All manufacturers can be pro-active using this index-led approach; it is where NPD is going to be at its most agile in responding to consumer demands and trends. Even so, such high-level policy remains relatively niche in application and there is patchy progress in improving health and sustainability[4]. It is clear that food manufacturers investing in improving health should be rewarded; how this will happen is uncertain, but some form of certification is likely to be involved[5].

Building sustainability

Even the public health community is admitting ‘our current approaches don’t work’ and so it is seeking new solutions[6]. Salt, sugar and five-a-day targets have all proven difficult to meet, raising the question as to why this is the case. Investigations within the sandwich category show how significant insights can be obtained from interpreting health, consumer demand and sustainability data. In starting this process, there is always an initial requirement to understand why there is a demand for a product, in this case sandwiches and convenience foods. The role of lifestyle and consumer experience must be put in the centre of the plate for improvements to take place. Such a re-thinking is far from unusual, it has already revolutionised fat consumption in the last decade with the emergence of low carbohydrate diets and low-fat or diversified fat diets (e.g. the Ornish and Mediterranean diets). Placing sustainability metrics into consumer choices offers a means to extend the reach of healthier diets and to reduce waste. However, this raises the question of whether such healthier choices result in a lower carbon footprint.

Making the carbon footprint of sandwiches relevant to consumers

One of the reasons we have not put both health and sustainability metrics at the heart of NPD in food is that the information required is still very fragmented and rarely made relevant for consumers. A recent Life Cycle Assessment (LCA) of the UK sandwich sector has provided the carbon footprint of sandwiches and has highlighted where gaps in NPD and sustainability reporting exist[7]. The study re-establishes that sandwiches using livestock product ingredients have a greater carbon footprint than those using only plant product ingredients. The

Figure 2 The use of plant proteins in a balanced diet offers sustainability positives and delivering fruit

and vegetables is an important target for the sector. Pulses, such as chickpeas, offer this plant protein and there are important nutritional advantages to
making pulses part of a balanced diet .

straightforward solution to reducing the carbon footprint of all sandwiches would be to substitute plant products in place of animal products. If it were not the case that the most popular sandwiches contain meat or dairy products, this would be a very good strategy for sustainability but, practically speaking, it would be a disaster for a sandwich business and the consumer. However, there are some recent innovations in the development of plant-based meat analogues that are getting close to being acceptable substitutes for ‘real’ meat. The economics of their demand is now similar to those of meat and this will continue to be highly disruptive if cultural demand continues to support meat free.

LCA methods often demonstrate such plant protein substitution scenarios as successes, but this is not the case for most businesses and consumers if they exclude choice. After all, manufacturers will want to encourage consumer choice because they invest in and wish to develop the ‘Goldilocks Product’ that is ‘just right’ for the marketplace. So, are sustainability and business going to be in conflict here? Not quite: the weighting of ingredient impact to the popularity of different types of sandwich introduces an important opportunity. The carbon footprint analyses show that refrigeration can be responsible for as much greenhouse gas emission as some of the ingredients. This is crucially important to manufacturers who have no control over consumer choice but do have control over how long products stay in the supply chain before consumption. This defines truly agile manufacturing when shelf life and availability of sale are perfectly matched; the LCA shows how this makes it possible to dramatically reduce the carbon footprint of sandwiches and chilled foods. If the supply chain inventory meets demand perfectly, the carbon footprint drops, meaning the most popular meat and dairy sandwiches need not be changed if the supply chain transaction for refrigeration is reduced.

We are immediately thrown into trade-offs between choice of ingredients and costs of refrigeration, which is typical of many LCA focused studies and this tends to confuse consumers. The priority at the point of sale is to ensure that consumer choices and the determination of costs for delivering those products, including refrigeration, is effectively a transaction that is ‘behind the label’. The only meaningful way to qualify this is by making sure that NPD meets these demands and that companies obtain accurate information about availability of product on service or retail shelves.

Accurate data on how long products remain on shelves is available and these are too often standardised by LCA techniques so that carbon footprints can be in danger of providing a poor relationship with consumer behaviour. There is currently no consumer carbon allowance or understanding of it and the sandwich industry could make such an understanding of carbon possible in the context of a healthy diet.

If the supply chain inventory meets demand perfectly, the carbon footprint drops, meaning the most popular meat and dairy sandwiches need not be changed if the supply chain transaction for refrigeration is reduced.

The supply of sandwiches - a case study identifying where to improve the carbon footprint of foods

Poor forecasting is typically identified as a cause of waste; increased food waste will increase the carbon footprint of a supply chain and technological solutions to improve this are currently available. The rise of Blockchain and Distributed Ledger Technologies provide a route to viewing what is going on in supply chains instantly[9]. This type of inventory surveillance has already been tested with high profile recall exercises that have drastically reduced the time between reporting a recall issue to completing the full traceability assessment of the product.

These systems are clearly cost effective because they reduce information processing time from days or hours to seconds; the method of responding to this information is still uncertain but they have improved the recall process dramatically. Many commentators are considering how these types of Distributed Ledger Technologies can be applied to needs within the food industry, such as food waste reduction.

If we can project which products are actually in the supply chain and being sold at any one time, instantaneously, then we should be able to implement more incisive waste reduction strategies to match supply to demand more accurately. The use of such Distributed Ledger Technologies provides many scenarios that are real opportunities for foods, such as sandwiches, where seasonal trends and swings in purchasing activity will often throw a few surprises for even the most experienced manufacturers and retailers.

The scale of food waste produced in supply is often uncertain, but sandwiches can account for 7% waste in a typical retail store[10]. The variability in demand for sandwiches is seasonal and often promotion-led by the meal-deals; popularity swings of up to 20% are not unusual. Projecting such dynamics depends on timely data acquisition because sandwiches have a two- to four-day shelf life. The sandwich supply chain system is constrained by this short time window so there is little opportunity to be flexible in ensuring products are available to sell. This is currently an all or nothing scenario – a fully stocked shelf is far more appealing to consumers – and it will change to one with far more options as inventory data becomes more timely for manufacturers and retailers[11].

Food manufacturers operate in a pivotal part of the supply chain, upstream are the food ingredient producers - farmers, growers and ingredient processors – and downstream in the supply chain are the consumer facing operations – distributors, wholesalers and retailers. This is a pinch point where producers want the highest prices for ingredients and the consumer facing operations want the lowest prices for manufactured goods so that these can be passed on to consumers.

Without open innovation, disruptive thinking and creative NPD, it is increasingly difficult for any food business to be viable at this pinch point, which is why building sustainability and waste reduction into NPD is essential. Convenience products are an im­portant group of foods that focus on meals and, as such, provide many opportunities to improve health and sustainability.

An NPD model that improves sustainability

Figure 3  New methods of integrating supply chains include innovative ventures, such as vertical farming systems that produce fresh ingredients for food-to-go items on existing manufacturing sites, that is food manufacturing facilities are also producing ingredients as well as manufacturing food products.

​NPD must respond to the information derived from supply chains; the new methods of working with more timely information will seek to re-define functions, such as greater sustainability and lower carbon footprints. This will be achieved before products are released for sale by determining the popularity for new sandwich recipes and new service formats via data concerned with sales and the time a product spends in the cool chain. This is being revolutionised by the technologies, such as big data, blockchain and the Internet of Things, that enable supply to meet demand because they reduce the amount of time a convenience food product remains refrigerated before consumption. The convenience and food on the go marketplace can be an important arena in which to test these technologies.

The impact of re-defining NPD this way will decrease the amount of food waste because sub-optimal quality product will not reach the retail sector or consumer. The convenience food sector is often characterised by ‘casual eating’ or ‘buy a lot, waste a lot’ descriptors but innovative NPD and supply chain management mean both of these terms simply do not apply.

The idea that convenience foods, such as sandwiches, provide a sustainable and healthy food choice can be in conflict with the environmental ranking of foods often provided by carbon foot-printing and LCA. This is because they spotlight specific issues rather than identify the solutions that are found when consumption data is properly considered. For example, the sales of food on the go, such as sandwiches, sushi and pasta salads, which are the growing trends in convenience food, are likely to be most popular in younger (16-24 years) age groups.

The opportunity to develop nutritionally balanced meals with this group provides high impact solutions for improving quality of life, health and sustainability outcomes in later life. The pressures placed on convenience and processed foods have changed; the sandwich category is at the forefront of this revolution where NPD is integrated with healthy and sustainable attributes[12]. The standard NPD model is also being disrupted by open innovation systems, where consumers use social media and other communications to essentially become part of NPD programmes. The convenience foods sector is looking to the next wave of food reformulation and it will be focused on eating responsibly. This will be reflected in what we do as shoppers where we are increasingly aware of what is behind the label.

Wayne Martindale*1, Mark Swainson2, Tom Hollands3 and Richard Marshall4

1 Food Insights and Sustainability, National Centre for Food Manufacturing University of Lincoln. Holbeach Campus, Park Road, Holbeach, PE12 7PT

2 National Centre for Food Manufacturing, University of Lincoln. Address as 1, above

3 Raynor Foods Ltd, 4 Farrow Road, Widford Industrial Estate, Chelmsford, Essex, CM1 3TH

4 Food Enterprise, Bath Spa University, Newton Park, Newton St Loe, Bath BA2 9BN



1.  Food system Framework (IFST) 2018, (accessed, 5th June 2018)

2.  Rooney, C., McKinley, M.C., Appleton, K.M., Young, I.S., McGrath, A.J., Draffin, C.R., Hamill, L.L. & Woodside, J. V. (2017). How much is “5‐a‐day”? A qualitative investigation into consumer understanding of fruit and vegetable intake guidelines. Journal of Human Nutrition and Dietetics, 30, 105–113.

3. Chatterjee, S., Khunti, K. & Davies, M.J. (2017). Type 2 diabetes. The Lancet, 389, 2239–2251.

4. Roberto, C.A., Swinburn, B., Hawkes, C., Huang, T.T.K., Costa, S.A., Ashe, M., Zwicker, L., Cawley, J.H. & Brownell, K.D. (2015). Patchy progress on obesity prevention: emerging examples, entrenched barriers, and new thinking. The Lancet, 385, 2400–2409.

5. Haddad, L. (2018). Reward food companies for improving nutrition. Nature, 556, 19–22.

6. Lee, A. (2016). Obesity: we need to move beyond sugar. The Lancet, 387, 199–310.

7. Espinoza-Orias, N. & Azapagic, A. (2017). Understanding the impact on climate change of convenience food: Carbon footprint of sandwiches. Sustainable Production and Consumption.

8. , accessed 9th July 2018.

9. Ge, L., Brewster, C., Spek, J., Smeenk, A., Top, J., Diepen, F. van, Klaase, B., Graumans, C. & Wildt, M. de R. de. (2017). Blockchain for agriculture and food. Wageningen Economic Research.

10. Mena, C. & Whitehead, P. (2008). Evidence on the role of supplier-retailer trading relationships and practices in waste generation in the food chain. Cranfield University: Cranfield, UK.

11. Mena, C., Terry, L.A., Williams, A. & Ellram, L. (2014). Causes of waste across multi-tier supply networks: Cases in the UK food sector. International Journal of Production Economics, 152, 144–158.

12. Poti, J.M., Mendez, M.A., Ng, S.W. & Popkin, B.M. (2015). Is the degree of food processing and convenience linked with the nutritional quality of foods purchased by US households?. The American Journal of Clinical Nutrition, 101, 1251–1262.

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