Enhancing olive oil quality through an advanced enrichment process utilizing ripe and fallen fruits

Enriched olive oil combines olive oil with plants for enhanced flavor and potential health benefits, offering a versatile culinary ingredient. This process combines the natural goodness of olive oil with the unique characteristics of plants. The aim of this work was to study the effect of rosemary (Rosmarinus officinalis) as a food additive (E 392) in the enrichment of ripe and fallen olives on the quality of the resulting flavored olive oil. Olive fruits at different stages of maturation green (ST1), mixed (ST2), black (ST3), and fallen in the ground (FO) were crushed with rosemary at two different percentages (2 and 5% w/w). Quality parameters, fatty acid profile, antioxidant profile, and volatile composition were evaluated. For ST3 and FO, rosemary addition decreased free acidity values, peroxide index, K₂₃₂, and pigment content. Total phenols increased by 34 and 55% for ST3 and FO, respectively with 2% rosemary. As for bio-phenols, this process influenced antioxidant activity. In fact, 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity is improved by 59 and 51%, respectively, for ST3 and FO oils flavored with 5% rosemary. As anticipated, the volatile profile changed significantly due to the rosemary addition, inducing the presence of terpene compounds, such as α-pinene, α-cymene, camphene, β-pinene, and α-terpineol. These findings prove that aromatization process improves the quality and the antioxidant profile of olive oils obtained from mature and fallen olives, and could help in solving the economic problems of oil mills. Other plants such as garlic, lemon, thyme, and others can be studied to find out if better results can be achieved.