Green Technologies and LCA for the Analysis of Bioactive Compounds in Wheat Husk: An Integrated Study for Sustainability Assessment

Wheat is the third most cultivated cereal in the world and is one of the most important cereals for production in the food industry. The FAO has estimated that its production worldwide is approximately 760 million tons, of which Europe produces approximately 33%. Wheat husk, which is the external leathery part of the grain, is one of the main by-products of the wheat supply chain. This low-cost by-product is unstudied and underutilized, although it is generated in abundance in wheat production (approximately 17–20% of grain yield). Therefore, it is important to extract residues of high nutritional value (e.g. polyphenols), thus valorizing agri-food by-products. For this purpose, the study will examine the possibility of recovering bioactive compounds (BCs) (e.g. polyphenols) from wheat by-products using green technologies (such as ultrasound-assisted extraction, natural deep eutectic solvents or NADES, water, etc.), which have been proposed to be greener replacements for conventional solvents (e.g. methanol, n-hexane, ethyl acetate). In particular, NADES will be applied for the extraction of BCs, as they are natural solvents compatible with food, pharmaceuticals, and cosmetics. Furthermore, the application of the life cycle assessment (LCA) methodology would allow a sustainability assessment for the recovery of bioactive components compared to wheat by-products.