Utjecaj maceracije na oksidativne promjene polifenolnih spojeva kod bijelih vina

master's thesis

• Title (english): The effect of msceration on the oxidative changes of polyphenols in white wine
• Author: Tamara Strižak
• Mentor: Karin Kovačević Ganić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology and Analysis of Wine); Zagreb
• Defense date and country: 2014-09-29, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Polifenolni spojevi su važne komponente vina i odgovorni su za njegovu boju, trpkoću, gorčinu i stupanj oksidacije. Da bi se smanjili negativni utjecaji oksidacije, tijekom proizvodnje vina dodaju se različiti antioksidansi. Također, u cilju poboljšanja kvalitete i organoleptičkih karakteristika, u proizvodnji bijelih vina primjenjuje se proces hladne maceracije koji doprinosi boljoj ekstrakciji polifenolnih spojeva. Cilj ovog rada bio je ispitati kako primjena maceracije i dodatak različitih antioksidansa utječu na koncentraciju polifenolnih spojeva i kvalitetu vina Pošip. Analizirani uzorci vina podvrgnuti su procesu hladne maceracije (15ºC/15h). Uzorci za analizu uzeti su: 48 h nakon taloženja mošta, nakon alkoholne fermentacije te nakon 3 mjeseca odležavanja u bocama. Vina punjena u boce tretirana su različitim antioksidansima. Za određivanje boje, ukupnih polifenola te tanina korištene su spektrofotometrijske metode, dok je za određivanje pojedinačnih polifenolnih spojeva korištena kromatografija visoke djelotvornosti (HPLC). Rezultati su pokazali da su macerirana vina podložnija procesu oksidacije. Veći intenzitet žute boje određen je u vinima starima 3 mjeseca u odnosu na uzorak mošta i vina nakon alkoholne fermentacije. Dodatak antioksidansa nije značajno utjecao na očuvanje polifenolnih spojeva.

Abstract (english)

Polyphenolic compounds are major components of wine and are responsible for its color, sharpness, bitterness, and degree of oxidation. To minimize negative effects of oxidation, different antioxidants are added during wine production. Also, in order to increase the quality and organoleptic characteristics, process of cold maceration is used in production of white wines, which increases the extraction of polyphenolic compounds. The aim of this study was to investigate how the process of maceration and the addition of different antioxidants affects the concentration of polyphenolic compounds and quality of Pošip wine. The analyzed wine samples were subjected to cryomaceration (15ºC/15h). Samples for analysis were exempted in time of 48h after deposition, after alcoholic fermentation and after 3 months of aging in bottles. Bottled wines were treated with various antioxidants. Spectrophotometric methods were used to determine the color, total phenols and total tannins. For the determination of individual polyphenolic compounds, HPLC chromatography was used. Macerated wines are susceptible to the process of oxidation. Wines which were aged for 3 months have a higher color intensity in comparison to musts and wines. Antioxidant addition did not have significant effect on the conservation of polyphenolic compounds.

• Keywords: polifenolni spojevi; oksidacija; maceracija; boja
• Keywords (english): polyphenolic compounds; oxidation; maceration; color
• Language: croatian
• URN:NBN: urn:nbn:hr:159:925430
• 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: Access restricted to students and staff of home institution
• Created on: 2017-05-02 10:50:51