Influence of dissolved oxygen on the quality of wine packaged in a multilayer, plastic and glass packaging materials

Abstract

U ovom radu praćen je utjecaj kisika na kvalitetu vina koje je bilo pakirano u staklenu (GL71), višeslojnu (PAP20, PELD; 84) i plastičnu ambalažu (PET) tijekom 128 dana. Kvaliteta vina određivala se praćenjem količine ukupnih polifenola, ukupnih antocijanina, ukupnih flavonoida, pH vrijednosti i ukupne kiselosti. Ukupni polifenoli određeni su Folin-Ciocalteau metodom, ukupni antocijanini pH-diferencijalnom metodom, a ukupni flavonoidi metodom s kompleksacijom flavonoid-aluminijev klorid. Konduktometrijska titracija upotrijebljena je za određivanje ukupne kiselosti prema vinskoj kiselini. Tijekom skladištenja otopljeni kisik mjeren je oksimetrom. Rezultati su pokazali da staklena ambalaža ne propušta kisik dok kod višeslojne ambalaže može doći do određene propusnosti kisika. Plastična ambalaža bila je propusna na kisik. Moguće je da je kisik uzrokovao određene promjene u vinu: smanjenje količine ukupnih polifenola i antocijanina, povećanje količine flavonoida i ukupne kiselosti. Promjene su bile statistički značajne samo kod smanjenja polifenola (višeslojna ambalaža), povećanja flavonoida (višeslojna i plastična ambalaža).In this work, the impact of dissolved oxygen on the wine quality packaged in glass (GL71), multilayer (PAP20, PELD; 84) and plastic packaging (PET) during 128-dayperiod was followed. The quality of wine was determined by monitoring the amount of total polyphenols, total anthocyanins, total flavonoids, pH and total acidity. Total polyphenols, total anthocyanins and total flavonoids were determined by using the Folin-Ciocalteau method, pH-differential method, and method with flavonoid-aluminium chloride complexation, respectively. Conductometric titration was used to determine the total acidity according to tartaric acid. Dissolved oxygen was measured by the use of oximetry. The results showed that oxygen did not permeate through glass packaging while in multilayer packaging oxygen permeability can occur to a certain extent. Plastic packaging was permeable to oxygen. It is possible that dissolved oxygen enhanced certain changes in wine: the decrease of total polyphenols and total anthocyanins, the increase of total flavonoids and total acidity. Only the decrease of total flavonoids (multilayer packaging) and the increase of flavonoids (multilayer and plastic packaging) was statistically significant