Full utilization of brewers' spent grain - Extraction of proteins and production of mycoproteins using emerging technologies

Abstract

The production of waste in the food industry is an environmental challenge and an opportunity for sustainable practices. Brewers' spent grain (BSG), a byproduct of beer production, is often underutilized despite its nutritional potential. Global beer production generates millions of tons of BSG annually, and its improper management can negatively impact industry sustainability. Rich in fibers and proteins, BSG is valuable for functional food ingredients, improving texture, stability, and nutritional value of foods. This project aims to develop an optimized process for protein extraction from BSG using ultrasound-assisted enzymatic extraction. Ultrasound, a non-thermal and environmentally friendly technology, enhances extraction process efficiency by facilitating cell structure breakdown and release of desired compounds. The combination of ultrasound with enzymatic hydrolysis is expected to improve protein solubilization, increasing yield and quality of the final product. Additionally, the study explores the use of fibrous residue from enzymatic extraction of BSG to produce mycoproteins, providing a sustainable substrate for cultivating fungi as an alternative protein source. The methodology involves drying and milling BSG, followed by ultrasound treatment and enzymatic hydrolysis, culminating in lyophilization of the supernatant to obtain the protein hydrolysate. The fibrous residue generated will then be used for fungal cultivation, resulting in mycoprotein production. This project aims to provide sustainable protein sources for the food industry, aligning with principles of sustainability and environmental responsibility.