Do-it-yourself approach applied to the valorisation of a wheat milling industry's by-product for producing bio-based material

Cereal processing and flour production play a key role in the Italian agrifood scenario generating valuable economic incomes and contributing significantly to the export market. The European Union's commitment to the transition towards the Circular Economic model has led to increasing attention to food by-products and waste valorisation practices in order to reduce the amount of food loss and waste and costs for disposal. Processing outputs produce secondary raw materials which often remain unexplored for alternative applications and other supply chains. This article focuses on the use organic residues obtained by cereal processing conducted by a small-size milling industry to produce bio-based materials. The research is structured in two stages: (1) the first investigates the production of organic waste through material flow analysis and characterisation of wheat dust, which is considered as waste, through nutritional and toxicological analyses; (2) the second explores the opportunity of using wheat dust as reinforcing filler for a starch-based bio-composite and as culture medium for a microbial cellulose. This second stage adopts the do-it-yourself (DIY) approach for upcycling of food waste and manipulation of bio-based materials. The wheat dust/starch bio-composite was processed to obtain surrogates of disposable plates, while the microbial cellulose was manipulated to achieve a film for food packaging. Strengths and criticalities of both applications are discussed, considering limitations implied by the DIY approach, and further implementations are defined. This article focuses on a case study located in Cuneo province (Piedmont Region, Italy), but it also considers the opportunity to upscale the study to larger milling industries due to the relevance of wheat grains processing in the Italian agrifood market.