Food processes are generally developed to ensure the best possible quality of the food products in mind. But they are not always very efficient in their use of water, energy and raw materials. Many processes use copious amounts of water, and this generates high energy usage as well, since the foods or food ingredients need to be dehydrated (dried) again. The waste water that is produced needs to be treated, because some of the raw materials is dissolved in the waste water. These raw materials are irrevocably lost. Also other waste streams are created, because of the focus of the process design on the primary product. Therefore, only a part, and sometimes even a small part of the raw material ultimately ends up on our plate. To improve this, you first need to know where the wasteful steps are located in a process. For this, you can use a range of methods. We use pinch technology and exergy analysis. Pinch will tell you how to optimise the use of a particular resource. Exergy analysis will tell you how efficient you use all your resources: raw materials, water, energy, or anything else. In addition, exergy is a thermodynamic quantity that is objectively defined; therefore the results of an analysis are completely objective. The next step is to re-design a process, using the analysis. Sometimes you can cascade resources (water, energy), but sometimes you need to think about doing different things. We run research projects that concentrate on the development of the methodology for this, but most of our research projects will carry out a sustainability / efficiency analysis at some stage, and therefore this work is shared by almost all our projects.
Sustainability of Human Nutrition
We can optimise food processes to need the least possible amount of resources for the production of a food product; however we should not forget that foods are consumed and digested. In the end, we should optimise the amount of resources that we need, not for a particular food, but for our nutrition. In some cases, the way of processing directly influences the efficiency of digestion. A well-known example is the lycopene in tomatoes. Eaten raw, this lycopene is hardly digested due to its crystalline state. After investment of some exergy (see above) in a process to make a sauce out of these tomatoes, the digestion of lycopene may increase by 400%. To absorb a certain amount of lycopene, therefore, you need a lot less raw materials, albeit at the cost of some processing. Similarly, proteins from animal origin are highly digestible and give us all the essential amino acids. Proteins from plants are much more sustainable to produce, but they are less digestible and do not contain all essential amino acids, and their processing also requires more resources. Therefore we study the use of resources in this complete chain, from agricultural raw materials, via ingredient and food processing, preparation by the consumer, and the digestive process, to find out how to optimise this complete chain. From this, we strive to understand how to fulfil our nutritional and sensory needs in the most efficient way, with respect to all resources at the same time: raw materials, water, energy, auxiliary chemicals, etcetera.