Life cycle assessment of wheat gluten powder and derived packaging film

This article presents a life cycle assessment (LCA) on wheat gluten materials. Two objectives form the motivation for this paper. First, the study provides an assessment of the environmental impact of wheat gluten powder production. The aim of this contribution is to provide a base assessment which can feed into the evaluation of any future wheat-gluten-based product. Second, the study evaluates wheat-gluten-based packaging film and compares it with low density polyethylene (LDPE) and polylactide (PLA) packaging film over the life cycle of these products. Scenarios including extrusion and casting for film production, incineration with energy recovery, and composting for end-of-life treatments are evaluated. Such comparison offers insight in environmental benefits of wheat gluten over conventional plastic film as well as its bio-based alternative and identifies its optimal production and disposal methods. For wheat gluten production, the LCA results show that the impacts of the wheat cultivation and gluten drying phase are dominant in the majority of the 18 impact categories in the ReCiPe midpoint assessment method. The LCA results also exhibit that the scenario with wheat gluten film produced by extrusion and incinerated to recover embodied energy is favorable from environmental perspective. It offers great benefits in climate change and fossil depletion over LDPE film and in 14 impact categories over PLA film. Although wheat gluten film suffers from common problems for bio-based materials (e.g. land occupation), the overall environmental performance indicates that wheat gluten provides a promising source for bio-based polymer production. (c) 2013 Society of Chemical Industry and John Wiley & Sons, Ltd