From cradle to grave: evaluating bread production and waste using multicriteria optimization and life cycle assessment

Bread is a fundamental staple in the diets of numerous nations. However, bread waste ranks among the most discarded food items globally, making a significant contribution to the ongoing challenge of global food waste. The impact of bread production and bread waste is assessed environmentally through multicriteria optimization, for carbon footprint, water footprint and cost. Two of the most consumed bread types, flat (pita) and yeast bread, are examined and are analyzed through life cycle assessment. The scope includes production stages and end of life alternatives including animal feed use, composting, incineration, and landfilling are examined. The results indicate that flat bread requires 674 m³ of water and produces around 721.86 kg CO₂ eq. per ton, while yeast bread requires 1379.86 m³ of water and emits 930.68 kg CO₂ eq. per ton. The wheat-milling process alone contributes to 75% of the carbon emissions. Animal feed from bread waste is most viable environmentally, saving 823.2 kg CO₂ eq. for each type of bread waste valorized. Prioritizing water and carbon footprints suggest the use of bread waste as animal feed. Conversely, composting and incineration with energy recovery emerge as optimal solutions when a greater emphasis is placed on cost allocation.