16 Sep The role of processed foods in a sustainable food system
There exist negative consumer perceptions on processed and ultra-processed foods, however such foods are commonly misunderstood. Here, we explore some of the reasons behind this, the varied definitions and types of processed foods, and how they are essential to the sustainability of the global food system.
Food processing is defined as making changes to a food to alter its earing quality or shelf life. Processed foods are often criticised and have a negative perception among consumers. A survey carried out by International Food Information Council found that 43% of consumers were not in favour of the consumption of processed foods.
The 2020 edition of the Global Nutrition Report claims that current food systems do not enable people to make healthy food choices, and one of the reasons for this is that highly processed foods are available, cheap and intensively marketed. They state that processed foods “high in added sugars, trans fats and salt, as well as low in fibre and nutrient-density” are now comprising a significant share of many diets globally, however they are not aligned with the World Health Organization’s definition of a healthy diet.
This is true for some ultra-processed, energy-dense and nutrient-poor foods. It is critical to minimise foods high in energy but low in essential nutrients and instead prioritise nutrient-rich foods. Many processed foods fit this description of nutrient-rich and can play an important role in a sustainable food system. Some foods classified as ‘ultra-processed’ by the Global Nutrition Report are processed for good reasons, with minimal impact on their nutrient content. Unfortunately, research shows that consumers have a limited understanding of what food processing is, and the important benefits it can provide.
Processed vs ultra-processed
The term “ultra-processed food” is problematic. A review of the use of this term found diverse inconsistencies in its use by policy and research, but almost exclusively with negative connotations and instructions to minimise their consumption. However, at least half of the US energy intake is from “ultra-processed foods”, by some definition, thus their avoidance or removal would be challenging.
The main aim of classifying foods under the category of ultra-processed and attempting to minimise their consumption is to reduce population intakes of free or added sugar, salt and other ingredients added to food during specific processes. This is an admirable goal, but requires consumer understanding of the differences between individual processed foods. Wholegrain bread, milk and frozen vegetables are all processed foods, but should be thought of differently by the consumer than a frozen pizza, high in energy and low in nutrient density.
Processed foods play a key role in nutrition and safety of food
The global population is growing, expected to reach almost 10 billion people by 2050. However, the planet is limited in its resources, creating a significant challenge to feed this growing population. Therefore, it is essential to optimise the efficiency of producing and distributing food, in order to ensure there is sufficient nutrient availability to meet global requirements. The DELTA Model tells us that based on current food production, there are already gaps against requirements for many essential nutrients – such as calcium and vitamin E – and these gaps could grow in size and number as the population does.
Processing can improve the nutritional quality of food. Processing can improve the bioavailability of essential nutrients – meaning more of the nutrient can be utilised by the human body. An example of this is processing legumes (via heat treatment, fermentation, germination or simply soaking) to increase the bioavailability of iron and zinc. Foods can also be fortified through addition of critical nutrients that may be limiting in some diets, as commonly performed for breakfast cereals. Processing therefore plays a key role in increasing nutrient availability to the growing global population.
In addition, many foods have a short shelf life. A variety of fruits and vegetables, as well as most animal-sourced foods, cannot be stored for long periods of time in their raw form. This can create potential food safety issues, or nutritional quality can decrease over time. Moreover, some regions do not produce sufficient food to meet the requirements or demands of their local population, meaning that it must be imported, taking time to reach those that need it. In addition, some food products are seasonal, where supply will exceed demand for some months of the year, and vice versa for the rest of the year.
It is therefore essential to extend the useful life of nutrient-rich foods to avoid safety issues and preserve nutritional quality. This can be achieved through processing. For example, raw milk has a relatively short shelf life, but this can be extended by processing it into milk powder, cheese or yoghurt. Milk is a nutrient-rich food, and processing allows as much of this nutrition to reach consumers as safely as possible. Likewise, freezing or canning of fruit and vegetables can keep these foods stable for as long as they remain in this state. Pressing oilcrops to produce vegetable oils allows the nutrients in these crops to be utilised in a wider variety of ways than the raw form allows. While some of these techniques are modern, such as freezing and canning, others, such as fermentation and pressing, have been instrumental in the human diet for millennia.
Processed foods help to increase equity of food distribution and reduce waste
There is a global issue of inequitable food distribution and food waste. The world produces enough food energy to feed nearly 9 billion people. The reason 1 in 9 people are hungry is due to inequitable distribution of food, caused by geographical and socio-economic factors.
Secondly, as explained above, processing can extend the useful life of foods. This can help to minimise food waste, as less will be thrown away due to perishability. A study performed in Austria found food waste can be reduced by six-fold when frozen foods are compared with fresh foods, while another found that frozen foods are wasted half as much as fresh foods. This in turn reduces the environmental impacts of food waste, and increases the availability of food. While frozen food supply chains are not available in all parts of the world, drying and canning can have similar outcomes.
While eliminating food waste is not the complete solution for a sustainable food system, it can play an important role in increasing the availability of nutrition to meet global requirements. Extending the shelf life of food also means it can be transported to regions that do not provide sufficient nutrients to sustain their local population. In addition, processing can improve the ease of this transportation. This plays a vital role in addressing the issue of equitable distribution of food.
Processing encourages consumption
Economic, cultural, and social factors will play an essential role in achieving a sustainable food system. Consumers must want to eat the food available to them, and be able to afford it. Food processing can help increase the convenience and variety of the foods available. Food processing can be used to improve the taste, texture and functionality of foods, encouraging consumption. This is particularly important for nutrient-dense foods containing critical nutrients that can often be limiting in diets. Processing can also help to reduce the cost of storing or transporting food, and seasonal price volatility, making nutrition more affordable.
Food processing plays a key role in the provision of adequate nutrition to feed a global population. Production and consumption of high-energy and nutrient-poor foods should be kept to a minimum, and consumers need to be able to recognise these foods without labels like “processed” or “ultra-processed”. Processing can help to improve the safety and nutritional quality of foods, reduce waste and improve distribution, and encourage consumption of nutrient-rich foods. Use of processing techniques for the right purposes should be encouraged.