Izolacija fenolnih spojeva iz komine masline

master's thesis

• Title (english): Isolation of phenolic compounds from olive pomace
• Author: Mirjana Cvitanić
• Mentor: Klara Kraljić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Oil and Fat Technology); Zagreb
• Defense date and country: 2016-07-05, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Kominu masline odlikuju visoke koncentracije fenolnih spojeva te ona može poslužiti kao dobra sirovina za njihovu ekstrakciju. Cilj ovog rada bio je optimirati brzi proces ekstrakcije fenola komine masline koristeći mikrovalove i ultrazvuk. Konvencionalnom metodom ekstrakcije po Soxhletu najviše koncentracije fenola u ekstraktu dobivene su nakon 3 sata. Koristeći mikrovalno-ultrazvučni ekstraktor, isti efekt ekstrakcije postignut je nakon svega 6 minuta, 30 puta brže. Snaga i vrijeme ekstrakcije utječu pozitivno, dok povećani udio metanola negativno utječe na ekstraktibilnost fenolnih spojeva. Korištenjem mikrovalova i ultrazvuka, osim na udio fenola, utječe se i na njihov sastav. Ekstrakcija mikrovalovima smanjuje koncentraciju vanilina, pinoresinola i p-kumarinske kiseline, a povećava koncentraciju hidroksitirosola, vanilinske kiseline, oleuropeina i tirosola u samom ekstraktu. Korištenje mikrovalova u kombinaciji s ultrazvukom smanjuje koncentraciju hidroksitirosola, vanilina i pinoresinola, a povećava koncentraciju vanilinske i p-kumarinske kiseline. Optimalni uvjeti za ekstrakciju ukupnih fenola iz komine masline mikrovalnom ekstrakcijom postignuti su sa 60 % vodenom otopinom metanola, pri trajanju ekstrakcije od 6 minuta i pri snazi mikrovalova od 300 W, a kod ultrazvučno-mikrovalne ekstrakcije postignut je vrlo sličan učinak pri istim uvjetima s 30 % manjom snagom.

Abstract (english)

Olive pomace is characterized by high concentrations of phenolic compounds and it can serve as a good raw material for their extraction. The aim of this study was to optimize a rapid extraction process using microwaves and ultrasound. Using conventional method, the highest concentration of phenols was obtained after 3 hours of extraction. By using microwaves and ultrasound similar concentration of phenols in the extract was obtained in only 6 minutes, 30 times faster. The use of microwaves and ultrasound, in addition to the yield of phenols, influences the composition of the phenolic compounds as well. In contrast to conventional methods, microwave extraction reduces the concentration of vanillin, pinoresinol and p-coumaric acid, and increases the concentration of hydroxytyrosol and vanillic acid, oleuropein and tyrosol in the extract. The use of microwaves and ultrasound reduces the concentration of hydroxytyrosol, vanillin and pinoresinol, but increases the concentration of vanillic and p-coumaric acid. It is shown that the strength of microwaves and duration of the extraction process have a positive effect, while the increasing proportion of methanol has a negative effect on the extractability of phenolic compounds. The optimum conditions for the extraction of phenols from olive pomace using microwave extraction were achieved with 60 % methanol solution, after 6 minutes of extraction and a microwave power of 300 W, while the ultrasound-microwave extraction method showed a very similar effect under the same conditions with 30 % less microwave power used.

• Keywords: komina masline; fenolni spojevi; ultrazvučno-mikrovalna ekstrakcija
• Keywords (english): olive pomace; phenols; ultrasound-microwave assisted extraction
• Language: croatian
• URN:NBN: urn:nbn:hr:159:425974
• Study programme: Title: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka prehrambenog inženjerstva (magistar/magistra inženjer/inženjerka prehrambenog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-04-27 10:29:37