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How will chemistry change our diets in the next 10 years?

David Julian McClements, Department of food science, University of Massachusetts, US 

Any change in our diets between now and 2020 will come down to a mixture of demographic, societal, economic, and scientific developments. The global population continues to grow and the fraction of the global population with more disposable income to spend on foods is increasing, particularly in Asia and South America. Consequently, the world will have to grow more food and use the food produced more efficiently. This will put an increasing strain on limited global resources, such as land, water and energy. Science and technology will play a key role in increasing the quantity and quality of foods available, and in ensuring that they are preserved, transported, and used efficiently. 

In developed countries, consumers are becoming increasingly concerned about the origin of their foods, the environmental and ethical implications of their food choices, and the impact of the foods they consume on their health. Some ’food activists’ appear to have an anti-science and anti-technology viewpoint, believing that all ’processing’ of foods is bad for you. 

I believe that the continued application of science and technology to food production will be critical to ensuring that the general population in 2020 has a broad range of healthy and affordable foods available. 

The potential benefits of applying science to foods can be demonstrated by one research area that is currently the focus of strong scientific interest: using structural design principles to create functional foods, which provide some benefit to humans over and above their normal nutritional requirements, For example, their consumption can help prevent chronic diseases such as diabetes, cancer, hypertension, osteoporosis, or cardiovascular disease. Researchers are using physical chemistry-based approaches (similar to those used in the pharmaceutical industry) to design structured delivery systems for ’nutraceutical’ components believed to promote human health (such as omega-3 fatty acids, phytosterols, and carotenoids). 

Researchers are also elucidating the fundamental physicochemical and physiological processes that occur when foods are consumed so as to create foods with enhanced sensory and/or nutritional qualities. For example, researchers are trying to identify how foods can be designed to induce the feeling of fullness by controlling their fate in the gastrointestinal tract. This kind of research is likely to change the nature of the foods that we consume in 2020, by providing foods that look and taste delicious, but that are also healthy, convenient, and affordable.

Herv? This, Co-creator of ’molecular gastronomy’ (with the late Nicholas Kurti), a physical chemist at the French National Institute for Agricultural Research, in Paris 

How will our diets have changed by 2020? By then, the global energy crisis could have sped the development of a new way of cooking using chemistry and its technology applications.

In the 1980s the physicist Nicholas Kurti and I introduced the scientific discipline of ’molecular gastronomy’, primarily to understand the chemical phenomena that occur during cooking. Molecular cuisine was created as an application of this. 

It is now time to move towards the next trend. Since 1994 I have been proposing ’note-by-note cuisine’, the equivalent of using synthesisers to make music instead of traditional instruments. In this form of culinary activity, the chef chooses every aspect of a dish and uses compounds (pure or mixtures) to build shape, colours, consistency, odours, taste, nutritional properties...

But how could the energy crisis contribute to the development of such a new way of cooking? For example, boiling wine to make a sauce uses a great deal of energy as the latent heat of water is high. What is more, odour molecules are lost through steam evaporation. Instead, if you mix the right compounds (tartaric acid, phenolics, glucose...) in the right amounts, you could get an ’equivalent’ of a reduced wine in seconds. 

It is only an example, but why ’cook’ at all? After all, food is something that we eat for energy, for body maintenance, for sensory stimulation, for cultural satisfaction. The use of heat is only needed for microbiological decontamination, consistency modification and the production of new taste or odorant compounds, and it could be avoided. Moreover, the use of compounds (pure or mixtures) could be socially more efficient, as mass production could be used to make the ’food ingredients’ for chefs.

A wonderful note-by-note dinner was served the day before the world opening sessions of the International Year of Chemistry and the new culinary technique has developed at a fast pace in the past year. 

It is not chemistry in the stricter sense, but an application of it. Chemistry was always useful through its application, and a lot of applications can still be found. 

Celebrate chemistry!

Gert Meijer, Vice-president of global nutrition and health, Head of Unilever nutrition network, Unilever R&D 

It is impossible to obtain the levels of micronutrients needed for optimal health by eating ’natural’ foods alone. Nutritionists have, in recent years, moved away from looking at micronutrient levels in terms of what we need just to prevent deficiencies and are now looking at the levels needed to optimise health. These micronutrient needs typically exceed the currently recommended levels.

By 2020 we hope to see a wide range of foods that have enhanced levels of micronutrients such as vitamin D, but lower energy content and significantly reduced levels of saturated fats, sugar and salt. But you can’t reduce the energy content of foods naturally while at the same time increasing micronutrient levels. You have to do this through food processing and through the application of chemistry. Chemistry is incredibly important in enabling us to make changes to the nutritional profile while maintaining product stability and taste. 

At Unilever, we have already used chemistry to provide healthier foods, such as margarine made using inter-esterification to give the lowest levels of saturated fats and high levels of essential fats. Typically, such spreads are also fortified with vitamin A and vitamin D. And we continue to try to reduce levels of saturated fats across our whole food portfolio. In an ideal world, by 2020 food products will be minimal in added sugar, saturated fats and trans fats. Achieving this will not be easy; we still need some saturated fats to give structure to certain foods. There is ample space for food chemistry to help create structuring components that would not deliver any calories, while removing the need for saturated fats. 

The big challenge is to make foods healthier whilst at the same time ensuring that they still taste great. Another challenge is overcoming the current consumer trend for ’natural’ foods. As nutritionists and food chemists we need to alter the perception that healthy foods are completely natural foods. We need to help consumers to understand that food processing and food chemistry are not techniques to be afraid of but can help to improve their health, giving them access to the micro- and macronutrients that they need.

Jennifer Norton, Tom Mills and Ian Norton, School of chemical engineering, University of Birmingham, UK 

The consumer of the future will demand healthier products that deliver the enjoyment and convenience of their current foods with lower environmental impact. If these challenges are to be met then a number of changes will occur in people’s diets. 

From a food structuring perspective we can consider four trends. First, ’healthy indulgence’ will start to become part of our everyday diet. Consumers have become accustomed to having indulgent foods,resulting in the consumption of too many calories. Science will develop ways of delivering the indulgence with fewer calories and added nutrients. An example exists in duplex emulsions, where some of the fat will be replaced by water (structured with natural biopolymers) as an internal droplet. The design will be to have the outer interface/fat structure experienced as fat, with the internal water phase ’invisible’ to the consumer.  

Salt enhances the taste and the acceptability of foods. Science will deliver methods of enhancing the experience of saltiness in lower salt products, relying on microstructure design to control the release rate of salt to the consumer’s taste buds. 

Saturated fatty acids cause a wide range of health problems. The crystal structure formed by saturated fats gives many foods their texture and storage stability. Science will find ways to extend the performance of the crystal structures (by including oils with crystalline behaviour), allowing saturated fats to be completely replaced by oils.  

More convenient ways to consume ’five-a-day’ will be coupled with both fat reduction and salt release technologies. Essential vitamins and minerals will be incorporated into the internal droplets and structures of foods, remaining hidden from the consumer on consumption. 

From an ingredient perspective there will be no, or very few, new ’chemicals’. There will be a need to use a wider range of natural ingredients in fabricated foods. The trick will be to find ways to make the natural ingredients function in physical chemical terms in the same way as current ingredients.  

Sustainability will point the food engineer towards local ingredients. This will bring big challenges as many ingredients will need to be replaced with molecules and materials extracted from local crops.  

Food engineers are already feeling the pressure from consumers to produce ’clean labels’, so that food products have shorter ingredient lists, with ingredients coming from natural sources. 

All these changes will depend heavily on physical chemistry, material science and novel/clever processing. Thus the future from a chemistry/chemical engineering perspective will be very challenging and exciting.