From Famine Food to a Functional Option

The practice of balanophagy has been documented since prehistoric times, particularly during periods of famine and warfare. Acorns from different Quercus species were an accessible, available and nutritionally valuable resource, primarily composed of carbohydrates, fiber and bioactive compounds, such as phenols and tocopherols. In the Mediterranean Basin, acorns were consumed roasted, as a coffee substitute, and in salty and sweet bakery products. In light of the historical and ethnocultural context, this research aims to enhance the added value of acorns by incorporating them into focaccia, a traditional Italian garnished flat bread. This product is recognized for its historical significance, production versatility, and capacity to meet the local needs and integrate alternative ingredients. The aim was to improve its nutritional profile, bioactive compound content, and physical properties. Two substitution levels - 15% and 30% acorn flour - were evaluated and compared to a wheat-based control formulation. Acorn flour increased the fiber content. In fact, the formulation containing 30% of acorn flour was a “source of fiber" (> 3 g/100 g), according to Reg. EU 1924/2006. Both acorn-enriched samples had a low predecited glycemic index (pGI) and were characterized by the presence of phenols, carotenoids, and significantly higher antioxidant activity compared to the control. Acorn flour influenced the color, imparting a brown hue, and the texture of focaccia, resulting in a denser crumb, due to gluten dilution. Overall, acorn focaccia represents a bridge between the past and the future, offering a promising strategy to promote the revival of acorns by combining tradition, innovation and sustainability.