Fizikalno-kemijska svojstva te fenolni sastav svježih i prerađenih jagoda

master's thesis

• Title (english): Physico-chemical senzoric attributes and phenolic compositions of fresh and processed strawberries
• Author: Vanja Đurica
• Mentor: Branka Levaj (mentor)
• 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: 2006-12-18, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

U ovom radu ispitivan je fizikalno – kemijski sastav jagoda sorti Clery, Honeoye i NF 421 te su od njihovih kaša pripremljene niskokalorične marmelade. Određeni su ukupni fenoli, neflavonoidi, flavonoidi, antocijani te antioksidativna aktivnost DPPH metodom. Metodom kvantitativne deskriptivne analize ocijenjena su senzorska svojstva svježih plodova, kaša jagoda i marmelada navedenih sorti. Marmelade su kuhane u vakuum kuhaču i pri atmosferskom tlaku u laboratorijskim uvjetima. U analiziranim kašama utvrđena je razlika u količini ukupne suhe tvari, topljive suhe tvari i pH vrijednosti. Preradom kaša u marmelade došlo je do smanjenja količine antocijana, ali to nije utjecalo na smanjenje antioksidativne aktivnosti. Svježi plodovi jagoda sorti NF 421 i Clery imale su bolje ocijenjenu slatkoću i harmoniju okusa. Kaša sorte Honeoye imala je kiseliji okus, intenzivniju aromu po voću, jači intenzitet mirisa i miris po jagodama od sorti Clery i NF 421. Marmelade kuhane u vakuum kuhaču ocijenjene su vrlo slično.

Abstract (english)

In this paper the analysis of physical and chemical compositions of strawberry cultivars Clery, Honeoye and NF 421 were determined and the low calory marmelades were prepared. The total phenolic, flavonoid, non-flavonoid, anthocyanin contents and antioxidative activity were determined in the mash and marmelades. Using quantitative descriptive analysis sensor attributes of fresh strawberries, their purees and marmelades were determined. Marmelades are prepared under vacuum conditions and under atmosphere pressure in laboratory conditions. Total soluble solids and pH values were different in the analyzed purees from the source. During the processing of purees into marmelades the amount of total anthocyanins was decreased but there was no influence on the antioxidative activity, which was quite remarkable. Fresh strawberries Clery and NF 421 had better sweetness and flavour marks. Puree made of strawberry Honeoye had a more sour taste, more intensive strawberry flavour, bigger intensity of flavour and friut aroma than the purees made of strawberries Clery and NF 421. Marmelades prepared under vacuum conditions were almost similar.

• Keywords: jagode; marmelade; QDA; antioksidativna aktivnost; antocijani
• Keywords (english): strawberries; marmelades; QDA; antioxidative activity; anthocyanins
• Language: croatian
• URN:NBN: urn:nbn:hr:159:358878
• Study programme: Title: Food Technology; specializations in: Nutrition; Course: Nutrition; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer prehrambene tehnologije; smjer nutricionizam (diplomirani inženjer prehrambene tehnologije; smjer nutricionizam)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-07 12:56:17