Utjecaj koncentracije i sastava nosača na inkapsulacijsku učinkovitost ekstrakta ružmarina (Rosmarinus officinalis L.) ionskim geliranjem

undergraduate thesis

• Title (english): The influence of concentration and composition of delivery systems on encapsulation efficiency of rosemary (Rosmarinus officinalis L.) extract using ionic gelation
• Author: Gabrijela Šišić
• Mentor: Draženka Komes (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Chemistry and Technology of Carbohydrates and Confectionery Products); Zagreb
• Defense date and country: 2017-09-08, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Zbog izrazite nestabilnosti i osjetljivosti biološki aktivnih spojeva pri uvjetima prerade i proizvodnje prehrambenih proizvoda, te niske biodostupnosti nakon konzumacije, razvijena je tehnika inkapsulacije. Cilj ovoga rada je ispitati utjecaj koncentracije alginata (4% i 5%) i sastava različitih nosača na inkapsulacijsku učinkovitost ekstrakta ružmarina primjenom ionskog geliranja. Kao osnovni nosač za inkapsulaciju polifenola ružmarina korišten je alginat (A) te njegove kombinacije s izolatima proteina sirutke (IPS) i zelenom kavom (ZK) kao novim materijalom u sustavu nosača za inkapsulaciju aktivnih spojeva. Formuliranim hidrogel česticama određene su fizikalno-kemijske i morfološke karakteristike, učinkovitost inkapsulacije polifenola i zadržavanja antioksidacijskog kapaciteta te profili otpuštanja polifenola i antioksidacijskog kapaciteta iz čestica u simuliranim gastrointestinalnim fluidima. Veća koncentracija alginata (5%) rezultirala je većim česticama sferičnog oblika te tvrđe i elastičnije teksture. „Jačanje” alginatnog gela s IPS i ZK pokazalo je povećanu inkapsulacijsku učinkovitost ukupnih polifenola i hidroksicimetnih kiselina te stupanj zadržavanja antioksidacijskog kapaciteta, kao i korištenje manje koncentracije alginata (4%) prilikom formulacije alginatnih sustava. Najveću inkapsulacijsku učinkovitost ukupnih polifenola imao je sustav A-ZK za obje korištene koncentracije alginata (93,91% - 4%; 92,07% - 5%), kao i najveću učinkovitost zadržavanja antioksidacijskog kapaciteta ABTS metodom. Najbolji profil otpuštanja svih ispitivanih parametara također je pokazao sustav A-ZK i time pokazao velik potencijal primjene zelene kave kao materijala u sustavu nosača za imobilizaciju biljnih polifenola.

Abstract (english)

Due to the high instability and sensitivity of bioactive compounds at the conditions of processing and production of food products, and low bioavailability after consumption, encapsulation technique was developed. The aim of this study is to investigate the influence of alginate concentration (4% and 5%) and composition of different delivery systems on encapsulation efficiency of rosemary extract using ionic gelation. Alginate (A) is used as a basic delivery system for encapsulation of rosemary polyphenols, and it is combined with whey protein isolates (WPI) and green coffee (GC) which is a new material for encapsulation of active compounds. Obtained hydrogel beads were investigated for physical-chemical and morphological properties, encapsulation efficiency of polyphenols and retained antioxidant capacity, as well as for release profiles of polyphenols and antioxidant capacity from hydrogel beads in simulated gastrointestinal fluids. Higher alginate concentration (5%) resulted in formation of bigger beads with more spherical shape, and harder and more elastic texture. Reinforcement of alginate gel with WPI and GC showed increased encapsulation efficiency of total polyphenols and hydroxycinnamic acids and retained antioxidant capacity, where the highest encapsulation efficiency of total polyphenols showed delivery system A-GC for both used alginate concentrations (93,91% - 4%; 92,07% - 5%), as well as the highest retention of antioxidant capacity using ABTS method. The best release profile of all tested parameters was also determined in system A-GC, thus showing a great potential of green coffee as a material in delivery systems for immobilization of plant polyphenols.

• Keywords: alginat; inkapsulacija; izolati proteina sirutke; polifenoli; ružmarin; zelena kava
• Keywords (english): alginate; encapsulation; green coffee; polyphenols; rosemary; whey protein isolates
• Language: croatian
• URN:NBN: urn:nbn:hr:159:310204
• Study programme: Title: Food Technology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka prehrambene tehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka prehrambene tehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-09-11 12:26:33