Unravelling the potential of Mediterranean citrus by-products: M.E.D.I.S.M.A.R.T. Project overview

Introduction: Citrus fruits, widely abundant and distributed worldwide, give rise to substantial by-product quantities, potentially reaching up to 120 million tons each year, being the Mediterranean region a key producer in this context. Specifically, within this geographical area, Portugal's citrus fruits cultivated under the Protected Geographical Indication (PGI) designation constitute a significant agricultural sector, which resulted in a production of approximately 398.83 thousand tons, in 2019 [1]. Nevertheless, the processing of these fruits results in significant waste materials such as seeds, peels, and pulp, which make up 45% to 50% of the fruit and contribute to environmental issues such as water and land pollution [2, 3]. This challenge is further exacerbated by the increasing global population, which exerts mounting pressure on our food systems. However, citrus by-products hold great promise as a source of bioactive ingredients, offering solutions to maximize food utilization, promote upcycling, and introduce innovative nutritional and health benefits [3]. This potential is especially evident in citrus peels, which are rich in valuable compounds like essential oils, fiber, and polyphenols. Objectives: Under the frame of the M.E.D.I.S.M.A.R.T. Project (Partners: UCP, NRC, SSICA, AMC, CRIFFC and Tarimaș) was aimed the development of a sustainable and integrative approach based on green chemistry principles to valorize different Mediterranean citrus by-products (orange; lemon, mandarin and grapefruit peels) in a way to promote circular economy within the industry.