Assessment of the energy and exergy efficiencies of farm to fork grain cultivation and bread making processes in Turkey and Germany

Energy and exergy efficiencies of the wheat and rye bread and hamburger bun making processes are assessed based on data from Turkey and Germany. Amount of the land required to produce the same amount of wheat in Turkey is 3.34 times of that required in Germany; this ratio is 2.30 for the rye grain. These results show that the efficiency of the conversion of the solar energy into the grain mass is low in Turkey. CDP (Cumulative degree of perfection) for the wheat and the rye grain production is 3.73 and 4.96 in Turkey, and 11.26 and 10.46 in Germany. Specific energy utilization for rye bread production is almost the same in Turkey and Germany; but it is 12% higher in Turkey for wheat bread and hamburger bun making. Hamburger bun production requires the maximum energy utilization due to the higher weight loss in baking. The rye bread production process requires the minimum energy utilization due to the lower energy input in the agriculture and higher efficiency in the flour production. The maximum exergy destructions occur during the milling and the baking steps.