magistrsko delo
Rok Opara (Author), Tatjana Košmerl (Reviewer), Nataša Poklar Ulrih (Mentor), Mojmir Wondra (Co-mentor)

Abstract

Namen magistrskega dela je bil ugotoviti vpliv dodanega resveratrola v vino modra frankinja na njegov antioksidativni potencial, senzorične lastnosti, barvo in stabilnost ostalih komponent. V delu nas je zanimal tudi vpliv dolžine tehnološkega postopka maceracije na ekstrakcijo resveratrola in ostalih fenolnih spojin iz grozdnih jagod. Ugotovili smo, da koncentracije trans- in cis-resveratrola v vinu naraščajo z daljšim časom maceracije. Najvišjo koncentracijo obeh spojin pa smo zabeležili po osemmesečni vinifikaciji. Maksimalno koncentracijo polidatina smo zabeležili že po šestih dneh maceracije, potem pa se je njegova vsebnost začela zniževati vse do konca maceracije in tudi med zorenjem verjetno zaradi hidrolize. Pri dodatku resveratrola v vino in modelno raztopino s podobnim vol. % alkohola in pH kot vino smo ugotovili, da je topnost in stabilnost resveratrola boljša v vinu. AOP se je tako ob dodatku resveratrola v vino kot modelno raztopino povišal, vendar v zelo majhnem obsegu. Z višanjem koncentracije dodatka resveratrola v vino se je zviševala njegova intenzivnost obarvanosti, boljša pa je bila tudi stabilnost spojine malvidin-3-glukozid. Pri višjih dodatkih resveratrola (150 in 200 mg/L) smo pri senzoričnem ocenjevanju barve in vonja dokazali pozitiven vpliv resveratrola, kjer smo izračunali statistično značilno razliko v primerjavi z vinom kontrola. Statistične značilne razlike pa ne moremo potrditi pri ocenjevanju bistrosti, okusa in splošnega vtisa vina. Z izvedbo postopka kapsulacije resveratrola v alginatne kapsule smo dosegli 49 % učinkovitost. Dokazali smo tudi, da je časovno sproščanje resveratrola bolj intenzivno v etanolnih raztopinah.

Keywords

vino;modra frankinja;kakovost vina;maceracija;fenolne spojine;resveratrol;flavonoidi;neflavonoidi;antociani;kapsulacija;senzorične lastnosti;antioksidanti;antioksidativni potencial;vpliv na zdravje;

Data

Language: Slovenian
Year of publishing:
Typology: 2.09 - Master's Thesis
Organization: UL BF - Biotechnical Faculty
Publisher: [R. Opara]
UDC: 663.251/.253:543.2/.9
COBISS: 4798840 Link will open in a new window
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Downloads: 585
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Other data

Secondary language: English
Secondary title: Influence of resveratrol addition on the antioxidant potential and sensory characteristics of Blaufränkisch wine
Secondary abstract: The purpose of the master's work was to determine the effect of resveratrol in wine Lemberger to its antioxidant potential (AOP), organoleptic characteristics, color stability and stability of other components of wine. In our work we are interested in the influence of the length of the technological process of maceration of the extraction of resveratrol and other phenolic compounds from the grapes. We have found that the concentration of trans- and cis-resveratrol in the wine increased by prolonged maceration. The maximum concentrations of both compounds were recorded after an eight month vinification. Maximum concentration of polydatin was observed already after six days of maceration, and then its level began to decline until the end of maceration and further maturation probably due to hydrolysis. The addition of resveratrol in wine and in model solution with similar alcohol content and pH value as wine, we have found that the solubility and stability of the resveratrol in the wine is better. AOP is so with the addition of resveratrol in the wine as in a model solution increased, but to a very small extent. With increasing concentration of the resveratrol addition in the wine was increasing its intensity of color; the better was the stability of the compounds of malvidin-3-glucoside. At higher additives of resveratrol (150 and 200 mg/L) at the sensory evaluation of color and odor demonstrated a positive effect of resveratrol, which were calculated statistically significant difference as compared with the control wine. The statistically significant difference could not be confirmed in assessing the clarity, taste and general impression of the wine. By carrying out the procedure of resveratrol encapsulation in alginate capsules was achieved 49% effectiveness. We have shown also that the time-release effect of resveratrol was more intense in ethanol solution.
Secondary keywords: wine;blaufränkisch;wine quality;maceration;phenolic compounds;resveratrol;flavonoids;non-flavonoids;anthocyanins;encapsulation;sensory characteristics;antioxidants;antioxidant potential;influence on health;
Type (COBISS): Master's thesis/paper
Study programme: 0
Thesis comment: Univ. v Ljubljani, Biotehniška fak., Oddelek za živilstvo
Pages: XII, 82 f., [14] f. pril.
ID: 10850842