prikaz prve stranice dokumenta Primjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije
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master's thesis
Primjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije
Zagreb: University of Zagreb, Faculty of Food Technology and Biotechnology, 2015. urn:nbn:hr:159:425848
Grđan, Mario
University of Zagreb
Faculty of Food Technology and Biotechnology
Department of Food Engineering
Laboratory for Food Processes Engineering

Institutional repository: Repository of the Faculty of Food Technology and Biotechnology

Cite this document

Grđan, M. (2015). Primjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije (Master's thesis). Zagreb: University of Zagreb, Faculty of Food Technology and Biotechnology. Retrieved from https://urn.nsk.hr/urn:nbn:hr:159:425848

Grđan, Mario. "Primjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije." Master's thesis, University of Zagreb, Faculty of Food Technology and Biotechnology, 2015. https://urn.nsk.hr/urn:nbn:hr:159:425848

Grđan, Mario. "Primjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije." Master's thesis, University of Zagreb, Faculty of Food Technology and Biotechnology, 2015. https://urn.nsk.hr/urn:nbn:hr:159:425848

Grđan, M. (2015). 'Primjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije', Master's thesis, University of Zagreb, Faculty of Food Technology and Biotechnology, accessed 28 July 2024, https://urn.nsk.hr/urn:nbn:hr:159:425848

Grđan M. Primjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije [Master's thesis]. Zagreb: University of Zagreb, Faculty of Food Technology and Biotechnology; 2015 [cited 2024 July 28] Available at: https://urn.nsk.hr/urn:nbn:hr:159:425848

M. Grđan, "Primjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije", Master's thesis, University of Zagreb, Faculty of Food Technology and Biotechnology, Zagreb, 2015. Available at: https://urn.nsk.hr/urn:nbn:hr:159:425848

Metadata
TitlePrimjena visokonaponskog pražnjenja za ekstrakciju steviozida i rebaudiozida A iz stevije
Title (english)Application of high-voltage discharges for extraction of stevioside and rebaudioside A from stevia
AuthorMario Grđan
MentorZoran Herceg (mentor)
GranterUniversity of Zagreb
Faculty of Food Technology and Biotechnology
(Department of Food Engineering)
(Laboratory for Food Processes Engineering)
Zagreb
Defense date and country2015-09-22, Croatia
Scientific / art field,
discipline and subdiscipline		BIOTECHNICAL SCIENCES
Food Technology
Abstract
Svrha ovog rada je utvrditi učinak plinske i tekućinske plazme na ekstrakciju steviozida i rebaudiozida A iz osušenog lišća stevije. Uzorci su tretirani uz tri nezavisne varijable - temperatura, protok i vrijeme kod plinske, odnosno temperatura, frekvencija i vrijeme kod tekućinske plazme, a za usporedbu je provedena ekstrakcija po Soxhletu. Eksperiment je dizajniran putem potpunog faktorijalnog plana, rezultati su obrađeni metodom odzivne površine (RSM), a steviozidi i rebaudiozidi su identificirani HPLC metodom. Oba tretmana plazmom ostvarila su u prosjeku 42% - 45% veći prinos od ekstrakcije po Soxhletu. Temperatura je kod plinske plazme imala značajan utjecaj na ekstrakciju dok drugi faktori kao i svi faktori kod tekućinske plazme nisu imali statistički značajan utjecaj. Došlo je do pada pH i porasta provodljivosti nakon obrade tekućinskom plazmom. Pretpostavlja se da mehanizam ekstrakcije uključuje elektroporaciju pod utjecajem pulsirajućeg električnog polja te oksidaciju biljnih stanica radikalima i vodikovim peroksidom uz djelovanje UV zračenja.
Abstract (english)
The purpose of this study is to determine the effect of gas-phase and liquid-phase plasma on extraction of stevioside and rebaudioside A from the dried leaves of Stevia. The samples were treated using three independent variables - temperature, flow, and time for gas-phase and temperature, frequency and time when using liquid-phase plasma. For comparison,Soxhlet extraction was carried out. The experiment was conducted using full factorial design, the results were analyzed with response surface methodology, and steviosides and rebaudiosides were identified by HPLC. Both plasma treatments achieved an average of 42% - 45% higher yield than the Soxhlet extraction. The temperature in the gas-phase plasma had a significant impact on the extraction while other factors as well all factors in liquid-phase plasma had no statistically significant effect. There was a drop in pH and an increase in conductivity after processing with liquid-phase plasma. It is assumed that the extraction mechanism includes electroporation under the influence of a pulsed electric field, oxidation of plant cells by radicals and hydrogen peroxyde , and UV radiation.
Keywords
Keywords (english)
Languagecroatian
URN:NBNurn:nbn:hr:159:425848
Study programmeTitle: 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 resourceText
File originBorn digital
Access conditionsAccess restricted to students and staff of home institution
Terms of useLicence In copyright icon
Created on2017-05-03 12:12:35