Acorns: From an Ancient Food to a Modern Sustainable Resource

Acorns, the seeds of oak trees, are pivotal in the Mediterranean region, historically serving as vital sustenance for wildlife and humans. Although traditionally used for livestock, in times of scarcity, acorns were also used in human diets together with their use in traditional medicine. In this review, we explore and deepen the multifaceted significance of oak species, consolidating nutritional data while emphasizing sustainable practices for modern dietary integration and potential applications in other areas, promoting long-term ecological balance. In the Mediterranean region, notable species are Quercus ilex, Q. faginea, Q. suber, and Q. coccifera, which differ in flavor, texture, and nutritional content. Rich in carbohydrates, acorns can contain up to 50% starch as well as amino acids, proteins, and lipids. This nutritional composition favors the preparation of flour for use in bread doughs or even diverse types of processing such as roasting, which makes it a substitute for coffee. Furthermore, acorn by-products, containing tannins, find applications in leather processing. This review highlights and summarizes in detail the nutritional potential, culinary adaptability, and diverse applications of acorns, emphasizing the need to preserve and utilize natural resources sustainably. In doing so, it sheds light on the often-overlooked value of these humble seeds.