**Federica Flamminii, Carla Daniela Di Mattia \*, Giampiero Sacchetti, Lilia Neri, Dino Mastrocola and Paola Pittia**

Faculty of Bioscience and Technology for Agriculture, Food and Environment, University of Teramo, Via Balzarini 1, 64100 Teramo, Italy; fflamminii@unite.it (F.F.); gsacchetti@unite.it (G.S.); lneri@unite.it (L.N.); dmastrocola@unite.it (D.M.); ppittia@unite.it (P.P.)

**\*** Correspondence: cdimattia@unite.it; Tel.: +39-0861-266947

Received: 1 July 2020; Accepted: 22 July 2020; Published: 24 July 2020

**Abstract:** This work aimed to study the physical, structural, and sensory properties of a traditional full-fat mayonnaise (≈ 80% oil) enriched with an olive leaf phenolic extract, added as either free extract or encapsulated in alginate/pectin microparticles. Physical characterization of the mayonnaise samples was investigated by particle size, viscosity, lubricant properties, and color; a sensory profile was also developed by a quantitative descriptive analysis. The addition of the extract improved the dispersion degree of samples, especially when the olive leaf extract-loaded alginate/pectin microparticles were used. The encapsulated extract affected, in turn, the viscosity and lubricant properties. In particular, both of the enriched samples showed a lower spreadability and a higher salty and bitter perception, leading to a reduced overall acceptability. The results of this study could contribute to understanding the effects of the enrichment of emulsified food systems with olive by-product phenolic extracts, both as free and encapsulated forms, in order to enhance real applications of research outcomes for the design and development of healthy and functional formulated foods.

**Keywords:** olive leaf polyphenols; encapsulation; functional food; mayonnaise; alginate/pectin beads; phenolic extract; food enrichment
