The manuscript was prepared to conduct a thorough analysis and deepen the understanding of sustainable food production and diets within the context of the challenges posed by intensive agricultural practices and their environmental impacts, as well as their effects on human health. The rapid growth of the human population necessitates an increase in food production to meet nutritional needs. However, increasing the production of animal-derived products, which are significant protein sources, is likely to worsen undesirable consequences, such as global climate change, greenhouse gas emissions, and a larger carbon footprint. Traditional farming techniques also contribute to environmental contamination due to the use of synthetic fertilizers and pesticides. Transitioning to a sustainable food production model that addresses food needs while protecting consumer health and the environment is crucial. The challenge for the food industry and research centers is to find and develop the production of alternative sources of protein. In addition to the technological problems that must be solved, there is consumer education focused on healthy eating and overcoming psychological barriers related to the consumption of new foods.

Black lime (Citrus × aurantiifolia) is a dried key lime product traditionally used in Middle Eastern cuisine, characterized by an intense sour taste, distinctive citrus aroma, and dark color. Owing to its content of dietary fiber and bioactive compounds, particularly phenolics, black lime powder (BLP) may represent a promising ingredient for food enrichment. This study characterized BLP and evaluated the effects of replacing 3–15% of wheat flour with BLP on the physicochemical, antioxidant, spectroscopic, and sensory properties of shortbread cookies. Compared with wheat flour, BLP contained higher levels of dietary fiber, ash, and phenolic compounds, with protocatechuic, p-coumaric, vanillic, and ferulic acids, as well as isovitexin and vitexin, among the predominant compounds. Increasing BLP addition increased ash, soluble and insoluble dietary fiber, total phenolic content (TPC), and radical-scavenging activity. At 15% BLP, total dietary fiber reached 10.53% of cookie dry mass, while TPC and ABTS and DPPH radical-scavenging activities were approximately 5.5-, 11.1-, and 28.9-fold higher than in the control, respectively. These compositional enhancements were accompanied by technological changes, including increased moisture content and water activity, reduced cutting force, darker and less yellow cookies, and changes in starch organization and gluten structure indicated by FTIR analysis. Overall acceptability remained comparable with the control at 3–12% BLP but decreased at 15%, with 6–9% providing the most favorable balance between sensory quality and compositional enrichment. These findings indicate that BLP can be used as a fiber- and phenolic-rich ingredient for shortbread cookie enrichment.