Harnessing the power of lemon by-products: transforming into functional food ingredients

Introduction: Citrus fruits are one of the most widely cultivated fruit crops and one of the most important products consumed in the Mediterranean region. The annual production of different types of citrus fruits was around 143 thousand tonnes in 2019, with lemons and limes accounting for around 20 thousand tonnes [1]. Industrial processes use only 45% of the total weight of the fruit, leaving a significant amount of waste, including peel (flavedo: 27%), pulp (albedo and endocarp: 26%) and seeds (2%) [2]. Lemon by-products are composed of significant amounts of bioactive compounds such as lemon phenolic compounds-rich extract (LPC) and lemon dietary fiber-based powder (LDF), which give them bioactivities related to food preservation, such as antimicrobial and antioxidant. These by-products can be utilized to create bioactive and functional ingredients for the meat industry, supporting the zero-waste initiative and advancing the principles of a circular economy. Main conclusions: Reformulated mortadellas demonstrated several benefits, including being a good source of dietary fiber and phenolic compounds; Lipid oxidation in all the samples were below the level of incipient rancidity (≥1.0) throughout the storage period. LDF effectively reduced residual nitrite levels by more than 50% over 28 days; The reformulated mortadellas were well accepted by the sensory panelists. This study successfully replaced potato starch and sodium ascorbate with lemon (dietary fiber and phenolic compounds), showcasing a promising alternative for healthier and functional meat products. The valorization of lemon by-products, represent promising sustainable food preservation solutions. This study also underlines the importance of turning waste into valuable resources in the global citrus industry, as a circular economy approach.