Terroir 2014 banner
IVES 9 IVES Conference Series 9 Polyphenol content examination of Tokaji Aszú wines

Polyphenol content examination of Tokaji Aszú wines

Abstract

 There are two important conditions which determine the nascency of particular Tokaj wines comulatively: 

  • distinctive savour and fragance called the „aszú” taste and caused by Botritis c.
  • Tokaj nature which come from the barrel and other special aging methods 

We must state that two conditions above are only prevalent in the case when the processed grapes are full or over ripened, besides following the Tokaj wines preparation criterions (grape variety, soil, microclimate, vintage, etc.). These two conditions mentioned before were followed up only sensory based analysis up to now, altough the study of chemical idetified compounds which confirms these are obviuos. This study about the investigatation of the polyphenol compounds biological effect, next to definiate the tirosol, one of the simple phenol content from these wines. The grape stem and wine contents are changing during the infection of Botritis c., also the aminoacid content is decreasing. It is therefore assumed that the Tyrosine content derived from amino acids present in lower concentrations in the Tokaji wines. The Tyrosol (p-hydroxyphenyl ethanol) belongs to the simple phenols compounds and generated oxidative decarboxylation of the alcoholic fermentation only. It is oenological significance in sensory value itself, because it have a bitter taste, which could give that bitter flavour over 25 mg/l concentration. 

Also could be detect a significant differences in the simple phenolic and polyphenolic composition from each vintages at same sugar content level. We continue our investigations worthwhile. It is important to determine the polyphenolic compounds due to their positive health effects and simple polyphenols, including the amount of Tyrosol too, which also keep track of the Tokaj wines.

DOI:

Publication date: August 18, 2020

Issue: Terroir 2014

Type: Article

Authors

S.D. Nyitrainé, B. Nagy, M. Kállay 

Corvinus University of Budapest, Institute of Viticulture and Oenology Department of Oenology H-1118 Budapest, Ménesi út 45. 

Contact the author

Keywords

Tokaj, polyphenol, aszú, wines, tyrosol, Botrytis

Tags

IVES Conference Series | Terroir 2014

Citation

Related articles…

Evoluzione stagionale delle temperature ed andamento della maturazione nel vitigno Aglianico: risultati di un quadriennio di osservazioni in Campania

In viticoltura, la comprensione dell’influenza della temperatura dell’aria sulla dinamica della maturazione assume importante rilievo in relazione all’ ottimizzazione dell’ epoca di raccolta da cui dipende in modo significativo la qualità del prodotto finale.

Consumer perception and preferences regarding grape varieties resilient to climate change

Innovative solutions have been developed for winemakers to adopt in their cultivation practices [1]. Two of the implementations addressed in this study are the use of strains adapted to arid climates (AAC) and the use of varieties resistant to fungal diseases (PIWIs).

Effect of ozone treatments in wine production of young and short-term aged white wines: destructive and non-destructive evaluation of main quality attributes

The main aim of WiSSaTech project (PRIN P2022LXY3A), supported by Italian Ministero dell’Università e della Ricerca and NextGenerationEU program, is to investigate eco-friendly and safe alternatives to sulphur dioxide (SO2) in wine production.

Light-struck taste in white wine: enological approach for its prevention

Light-struck taste is a defect prevalent in white wines bottled in clear glass light-exposed for a considerable amount of time leading to a loss of color and appearance of sulfur-like odors. The reaction involves riboflavin (RF), a highly photosensitive compound that undergoes to intermolecular photoreduction by the uptake of two electron equivalents from an external donor, the methionine. The reaction includes different steps forming methional which is extremely unstable and decomposes to methane thiol and acrolein. The reaction of two molecules of methane thiol yields dimethyl disulfide. Methane thiol is highly volatile, has a low perception threshold (2 to 10 µg/L in wine) and confers aroma-like rotten eggs or cabbage.

Influence of trellis system and shoot density in yield and grape composition of a vineyard of Cabernet Sauvignon, in warm climate

In vineyards grown in warm areas, it is usual that the stage of maturity of the grapes is fast and easily reach a high concentration of sugar and low acidity, but not a adequate phenolic maturation. The geometry of the trellis system and the shoot density can modify the microclimate of the cluster and, therefore, the maturation process.