Functional food development using olive pomace phenolics and hydrogels

Abstract

Although the health effects of olive phenolics, hydroxytyrosol (HX), are well known, their utilisation is not at the forefront of the phenolics market. Besides, 99% of olive phenolics are lost during olive oil production (2.2 million tons year−1). This study aims to develop a functional hydrogel for functional foods using commercial olive powder derived from olive mill wastewater and methylcellulose (MC). The final hydrogel recipe, a multi-hydrocolloid recipe (MC and gelatine with low gelling temperature) based on minimum HX loss and acceptable sensory properties, was created by examining interactions of HX with salt, sugar, and citric acid in MC by a modified UPLC-UV method and expert sensory panellists. Finally, two dairy bases were created for the hydrogel with the best aroma match, and consumer-accepted dessert (72%) and appetiser (58%) providing the health claims of European Food Safety Authority (EFSA) (2 mg day−1 of HX) were produced. Moreover, a sample methodology has been developed.