Primjena hiperoksidacije u proizvodnji vina 'Chardonnay' i 'Traminac'

master's thesis

• Title (english): Use of hyperoxidation on 'Chardonnay' and 'Traminac' wine production
• Author: Maja Sošić
• Mentor: Ana Marija Jagatić Korenika (mentor)
• Committee member: Ana Marija Jagatić Korenika (predsjednik povjerenstva)
• Committee member: Ana Jeromel (član povjerenstva)
• Committee member: Marin Mihaljević Žulj (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Department of Viticulture and Enology); Zagreb
• Defense date and country: 2019-04-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Veliki izazov u proizvodnji bijelih vina predstavlja oksidacija – utjecaj kisika, koja može uzrokovati tamnjenje njegove boje te razvoj nepoželjnog mirisa i okusa. Za navedenu manu vina odgovorna je grupa spojeva - polifenoli, koji su podložni enzimatskoj te neenzimatskoj oksidaciji.
Cilj ovog pokusa bio je inducirati oksidaciju direktnim izlaganjem mošta kisiku, kako bi se pokrenuo rad oksidativnih enzima te stvorili tamni polimeri fenolnih spojeva koji se talože te ih je na taj način moguće ukloniti prije početka alkoholne fermentacije kako bi se spriječila oksidacija tijekom daljnje proizvodnje vina. Pokus je obavljen na moštu sorata ´Chardonnay´ i ´Traminac´, proizvedenih na znanstveno-nastavnom pokušalištu ''Jazbina'', Agronomskog fakulteta Sveučilišta u Zagrebu. Rezultati analiza osnovnog kemijskog te pojedinačnog polifenolnog sastava, hiperoksidiranih moštova i vina, uspoređeni su s kontrolom na kojoj se provodila uobičajena vinifikacija s dodatkom SO2, bez izlaganja kisiku.
Osnovna kemijska analiza pokazala je kako su parametri proizvedenih vina unutar uobičajenih, propisanih raspona vrijednosti za bijela vina. Kod obje sorte uslijed oksidacije se povećala pH vrijednost te alkoholna jakost vina. Rezultati nisu bili ujednačeni kod obje sorte, ali svakako je vidljiv utjecaj na koncentraciju katehina, kaftarne i galne kiseline te glukozida kvercetina. Pokus na vinu ´Chardonnay´ nije završio s očekivanim rezultatima, dok je kod vina ´Traminac´ hiperoksidacija imala značajniji utjecaj, pri čemu su reducirane kaftarna, kutarna, kavna i kumarna kiselina te procijanidin B1.

Abstract (english)

Oxidation represents a big challenge in white wine production because it can cause darkening of wine's color and development of unwanted aromas and flavors. Polyphenols – a group of chemical compounds, are also responsible for this wine fault since they are susceptible to enzymatic and non-enzymatic oxidation.
The objective of this experiment was to induce oxidation trough directly exposing wine juice to the oxygen so it can initiate oxidation enzymes activity and create dark polyphenol polymers that will sediment so it's possible to remove them before alcoholic fermentation starts and therefore prevent oxidation during further wine production. The experiment was made on the wine juice of 'Chardonnay' and 'Traminac' grape varieties, that were vinified on experimental station ''Jazbina' which is part of Faculty of Agronomy and Zagreb University. Results of primary chemical, as well as individual polyphenol composition of hyperoxidized juice and wine, were compared with the control wine and juice which were made with standard vinification that includes the addition of SO2 and no contact with oxygen.
Primary chemical analysis showed that concentration of wine compounds is accordant with standard and regulated limits for white wines. Both varieties showed increased pH value and alcohol content as an oxidation outcome. Collected results were not uniform for both of the varieties but there is a clear influence of oxidation on the catechin concentration, caftaric and gallic acid, as well as the quercetin glucoside. Experiment on the 'Chardonnay' wine didn't end up with expected results, while oxidation of 'Traminac' wine had more influence on polyphenol composition because of the reduced concentration of caftaric, coutaric, caffeic and cumaric acid, as well as the procyanidin B1.

• Keywords: hiperoksidacija; kisik; fenolni spojevi; 'Chardonnay'; 'Traminac'
• Keywords (english): hyperoxidation; oxygen; phenolic compounds; 'Chardonnay'; 'Traminac'
• Language: croatian
• URN:NBN: urn:nbn:hr:204:112800
• Study programme: Title: Horticulture; Study programme type: university; Study level: graduate; Academic / professional title: magistar/ magistra inženjer/inženjerka hortikulture (magistar/ magistra inženjer/inženjerka hortikulture)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-04-26 09:10:47