Environmental Evaluation of New Brewer’s Spent Grain Preservation Pathways for Further Valorization in Human Nutrition

• DOI: 10.1021/acssuschemeng.0c04236
• Publication Date: 2020-11-10T22:34:34Z
• Authors: Gaëlle Petit; Emilie Korbel; Vanessa Jury; Mohammed Aider; Samira Rousselière; Luc K. Audebrand; Sylvie L. Turgeon; Sergey Mikhaylin
• Keywords: 2. Zero hunger; 600; 04 agricultural and veterinary sciences; 7. Clean energy; 12. Responsible consumption; Beverages; Food; 13. Climate action; [SDV.IDA]Life Sciences [q-bio]/Food engineering; 8. Economic growth; 11. Sustainability; Grain; Plant derived food; 0405 other agricultural sciences; Materials; [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition

To tackle the issue of preserving natural resources and reducing pollution, the circular economy has been identified as a lever to ensure food security for 9 billion people by 2050. In the brewing sector, the annual production of wet spent grain represents 8 million tons in Europe and 40 million tons worldwide. This deposit represents a major opportunity in the current context of sustainable food transition, as it is an important source of protein, fiber, and other nutrients for human nutrition. Several initiatives regarding the valorization of brewer’s spent grain are emerging in human food, but studies to assess the environmental impact of different scenarios are still missing. Indeed, numerous separate or combined treatments could be involved in spent grain stabilization. The evaluation of the separate pathways identified could help to clarify the choices made by future economic actors willing to start a new activity or any researcher or manager willing to participate in a project to exploit the spent grain in food. The objective of this article is to conduct a comparative study of the environmental performance of different brewing grain stabilization engineering strategies among dehydration, separation, lactofermentation, freeze-drying, refrigeration, freezing, methanation, composting, and use for animal feed. These processes or their combinations for spent grain upcycling in human consumption will be examined by life cycle assessment, an ISO-standardized accounting methodology for quantifying the environmental impacts of a product. To our knowledge, this study is the first to include an environmental impact assessment of the spent grain stabilization pathways. The influence of the introduction of a new step in the life cycle of the upcycled spent grain on the environmental load of the product is highly significant. The results highlight the importance of strategic choices of stabilization processes and process coupling, a major step for spent grain reuse in human nutrition. This study provides trends and recommendations on parameters to be compared for technical and organizational strategies for byproduct valorization in food in the context of the circular economy.