Energy flows and greenhouses gases of EU (European Union) national breads using an LCA (Life Cycle Assessment) approach

The study has pinpointed the importance of evaluating food, in terms of environmental sustainability, with more than one type of functional unit in order to account not only for the bread's nutritional purposes but also the need to satisfy social, cultural, hedonistic and other qualitative functions. Specifically, when using a mass based functional unit, the less impactful results involve bread types with simple recipes, based essentially on flour, yeast and water. By assessing the breads with an energy based functional unit, bread types which also contain vegetable oils and small amounts of animal based ingredients result as more carbon and energy friendly. The use of a price based functional unit indicates that the higher priced bread types, manufactured with more expensive ingredients that are produced in an environmentally efficient manner, are the more sustainable ones. Overall, for many types of bread, the energy consumption during the production phase, in particular the baking process, represents a hot spot and is dependent on the size and shape of the bread. Furthermore, the efficiency of ingredient production (in terms of material and energy use and in terms of the respective yields of each nation in the European Union), such as that of milk and flour, also influences the sustainability of the bread types.