Extrusion Processing of Biomass By-Products for Sustainable Food Production

The sustainability of the food supply chain is gaining increasing attention in the quest to balance economic, environmental, and social dimensions. A key opportunity to enhance food system sustainability is by addressing food waste through upcycling strategies to generate higher value, functional foods. Extrusion is a food manufacturing technology that is emerging as a promising option for the incorporation of various types of biomass by-products, such as fruit and vegetable pomace, brewer’s spent grain, bagasse, and oil press cake. In this chapter, we present an overview of the latest research conducted on incorporating biomass by-products into extruded food products, with an emphasis on the challenges and opportunities associated with this approach. A meta-analysis study was conducted regarding a key challenge for product quality when incorporating by-products, which is the reduction in radial expansion index of expanded snack and breakfast cereal products. To highlight future opportunities, two case studies illustrate successful examples of by-product incorporation for commercial extruded food products, while emerging protein sources from waste-consuming insects were also explored. Overcoming these challenges and leveraging opportunities can contribute to a more sustainable food system through the integration of by-products into value-added extruded foods