The effect of the use of emulsion systems on the potential of phenolic extracts from blueberry on the prolongation of the oil oxidative stability : diploma thesis

Kultivirana borovnica (Vaccinium corymbosum L.) predstavlja jedan od najbogatijih prirodnih izvora polifenola u prehrani čovjeka. Raznolikost biološkog potencijala polifenolnih spojeva potvrđena je rezultatima brojnih znanstvenih studija. U ovom je istraživanju ispitan utjecaj fenolnih ekstrakata dobivenih iz svježih plodova te nakon različitih načina obrade plodova borovnice (liofilizacija, pasterizacija, obrada ultrazvukom visokog intenziteta) na povećanje oksidacijske stabilnosti ekstra djevičanskog maslinovog ulja. U cilju povećanja biološkog potencijala fenolnih ekstrakata u kombinaciji s njima korištene se dvije vrste emulzija tretirane postupkom mehaničke homogenizacije i ultrazvukom visokog intenziteta. Oksidacijska stabilnost ekstra djevičanskog maslinovog ulja mjerena Rancimat uređajem pokazala je značajan porast primjenom smjese emulzija i ekstrakata borovnice u odnosu na primjenu čistih fenolnih ekstrakata borovnice.Cultivated blueberry (Vaccinium corymbosum L.) represents one the richest natural sources of polyphenols. Numerous studies reported a huge range of biological potential of polyphenols. The aim of this study was to determine the effect of phenolic extracts from cultivated blueberry obtained from raw plant material as well as from plant material treated by different techniques (pasteurization, freeze-drying and the use of high intensity ultrasound) on the oxidative stability of extra virgin olive oil. In order to enhance the biological potential of different phenolic extracts from blueberry, the application of oil in water emulsion system was used. Prepared emulsions have been treated by mechanical homogenization and ultrasound of high intensity . Results showed that the oxidative stability of extra virgin olive oil measured by Rancimat apparatus was significantly prolonged after the use of phenolic extracts with emulsions