Bioaktivni sastav i antioksidacijski kapacitet Kombucha napitaka

master's thesis

• Title (english): The bioactive composition and antioxidant capacity of Kombucha beverages
• Author: Darija Gašpar
• Mentor: Danijela Bursać Kovačević (mentor)
• Mentor: Anica Bebek Markovinović (pomoć pri izradi, neposredni voditelj)
• Committee member: Jadranka Frece (predsjednik povjerenstva)
• Committee member: Tomislav Bosiljkov (član povjerenstva)
• Committee member: Ksenija Markov (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology of Fruits and Vegetables Preservation and Processing); Zagreb
• Defense date and country: 2024-11-29, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog rada je bio ispitati utjecaj skladištenja pet Kombucha napitaka na stabilnost polifenolnih spojeva i antioksidacijski kapacitet. Kao tradicionalni supstrat korišten je crni čaj, dok su Yerba Mate, ocat, smjesa Yerba Mate i Sencha te drijenak korišteni kao alternativni supstrati. Tijekom skladištenja na 4 ℃ kroz 7, 14 i 21 dan, analizirane su promjene u udjelima ukupnih fenola, flavonoida, hidroksicimetnih kiselina, flavonola, monomernih antocijana i proantocijanidina te antioksidacijskom kapacitetu (ABTS i FRAP). Rezultati pokazuju da je uzorak s octom imao najviši sadržaj bioaktivnih tvari i antioksidacijski kapacitet. Skladištenje je u većini uzoraka utjecalo na povećanje udjela ukupnih fenola i hidroksicimetnih kiselina, dok su udjeli flavonoida ostali nepromijenjeni. Sadržaj ukupnih flavonola povećavao se do 14. dana skladištenja, nakon čega je došlo do pada, te je u većini uzoraka zabilježeno smanjenje udjela proantocijanidina. Utjecaj skladištenja na antioksidacijski kapacitet bio je varijabilan, ovisno o metodi analize i supstratu.

Abstract (english)

The aim of this study was to examine the effect of storage on the stability of polyphenolic compounds and antioxidant capacity in five Kombucha beverages. Black tea was used as the traditional substrate, while Yerba Mate, vinegar, mixture of Yerba Mate and Sencha, and Cornelian cherry were used as alternative substrates. During storage at 4°C for 7, 14, and 21 days, changes in the levels of total phenols, flavonoids, hydroxycinnamic acids, flavonols, monomeric anthocyanins, proanthocyanidins, and antioxidant capacity (ABTS and FRAP) were analyzed. Results indicated that the vinegar-based sample had the highest content of bioactive compounds and antioxidant capacity. Storage generally led to an increase in total phenols and hydroxycinnamic acids in most samples, while flavonoids remained stable. Total flavonols increased until day 14 and decreased in proanthocyanidins was observed in most samples. The effect of storage on antioxidant capacity varied, depending on the analysis method and substrate used.

• Keywords: Kombucha napitak; bioaktivni spojevi; antioksidacijski kapacitet; skladištenje
• Keywords (english): Kombucha beverage; bioactive compounds; antioxidant capacity; storage
• Language: croatian
• URN:NBN: urn:nbn:hr:159:851035
• Study programme: Title: Food Safety Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane (magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-12-10 10:35:23