Vegan burgers fortified with agri-food by-products: nutritional enhancement, energy consumption and LCA

Abstract

The agri-food industry faces significant challenges in waste management, with by-products from fruit and vegetable processing contributing to a considerable environmental footprint. This study addresses these issues by exploring the innovative upcycling of fruit and vegetable by-products as a sustainable source of dietary fiber to fortify vegan burgers. We developed novel formulations by incorporating by-products from prickly pears, artichokes, carrots and broccoli and systematically evaluated their impact on product quality. Our research focused on three critical aspects: sensory analysis, nutritional evaluation, and environmental impact. The results reveal that incorporating these sustainable ingredients significantly enhanced the nutritional profile; specifically, the prickly pear peel fortification led to the highest antioxidant activity (5.40 ± 0.19 mg Trolox per g for ABTS and 24.14 ± 1.43 µmol Fe(II) per g for FRAP). From an environmental point of view the significant energy requirement to dehydrate and grind by-products contributes to the overall environmental burden of the new vegan burger formulations. In particular, the CTRL formulation exhibited the lowest carbon footprint (0.90 kgCO₂eq per FU), compared with formulations containing artichoke by-products (1.02 kgCO₂eq per FU), turnip tops by-products (1.10 kgCO₂eq per FU), carrot peel by-products (1.25 kgCO₂eq per FU), prickly pear peel by-products (1.31 kgCO₂eq per FU), and broccoli by-products (1.85 kgCO₂eq per FU). These results highlight the importance of considering the energy demand to ensure environmentally sustainable recycling processes. Although this strategy is a promising direction for the future of food production, the economic viability requires further optimization.