Valorisation of raw materials and process efficiency
Society is increasingly demanding sustainability. People are becoming steadily more aware of the environmental pressure caused by food production, a major human activity. Resources become scarcer, ecosystems are endangered, and the impact of climate change is a major issue of debate in the scientific community. This situation is not only caused (in part) by food production, but, conversely, affects it too. The project aimed to supply the key players in the food sector with a scientific approach to quantify the sustainability of their current and future processes and food chains.
In the project, an exergy-based method was used to quantify the resource efficiency of food processes and of entire food chains including waste streams. Multi-criteria decision models (MCD models) were developed. These will enable actors in the food chain to handle conflicting issues, such as quality and cost, that often arise when optimising their activities in a resource-efficient way. The exergy analysis and MCD models were applied in two different food chains for bread and mushroom respectively.
We have confirmed that exergy analysis is an excellent approach to assessing resource efficiency in these chains. The exergy evaluation of alternatives, for example the recycling of bread leftovers, showed that there is a trade-off between the exergetic gain of the actual recycling and the exergetic investment required to make the recycling possible. The MCD models indicated the possibility of optimising bread production and recycling, so that the overall resource efficiency of the chain improved significantly.