 IVES 9 IVES Conference Series 9 The relationship between enzyme treatment and polysaccharide extraction in wine making, and subsequent sensory effects in Cabernet Sauvignon wines

The relationship between enzyme treatment and polysaccharide extraction in wine making, and subsequent sensory effects in Cabernet Sauvignon wines

Abstract

AIM: To determine the effect of both ripeness and enzyme maceration on the astringency and bitterness perception of Cabernet Sauvignon winesRecent work has contributed to a more detailed understanding of the grape cell wall deconstruction process from ripening through crushing and fermentation, providing a better understanding of what role polysaccharides play in post-harvest fermentation of grapes(1,2). Current research on glycomics in red wine making suggest polysaccharides are important sensory impact molecules (3–6).

METHODS: Our experimental system harvests Cabernet Sauvignon grapes at three different ripeness levels and makes wine both with and without enzyme treatment. Using glycan-array technology (Comprehensive Microarray Polymer Profiling – CoMPP) as an analytical tool, we explore comparative levels of polysaccharides derived from cell walls that pass through the fermentation process to wines. These results are confirmed using GC-MS analysis of hydrolyzed polysaccharides, in addition to analysis of extracted tannins and polyphenols. Wines are submitted for sensory analysis to test astringency and bitterness perception after alcohol level equalization, providing a novel look at emzyme macerations sensory effect, focusing on polysaccharide levels in wine.

RESULTS/DISCUSSION: Data shows ripeness has a more limited effect than expected on polysaccharide profiles in finished wine, but enzyme addition causes a marked decrease in soluble polysaccharides. An increase in polymeric pigments and tannins is noted with enzyme use. Sensory testing of these wines established a relationship between perceived astringency and polysaccharide, but also shows the traditionally accepted relationship between phenol content of red wines and perceived astringency is more complicated.

CONCLUSIONS:

Enzyme maceration has an effect on perceived astringency in finished wines, but does not affect bitterness. Ripeness has a limited effect on polysaccharide extraction, but no significant differences in wine astringency. In this study, bitterness was not affected by ripeness nor enzyme maceration.

DOI:

Publication date: September 24, 2021

Issue: Macrowine 2021

Type: Article

Authors

Brock Kuhlman, Bodil JØRGENSEN, José L. ALEIXANDRE TUDO , John P. MOORE,

South African Grape and Wine Research Institute, Stellenbosch University, Stellenbosch, South Africa, Plant Glycobiology, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark , Universitat Politecnica de Valencia, Instituto de Ingenieria de Alimentos para el Desarrollo (IIAD), Departamento de Tecnología de Alimentos and Stellenbosch University, South African Grape and Wine Research Institute (SAGWRI), Department of Viticulture and Oenology Wessel DU TOIT, Department of Viticulture and Oenology, Stellenbosch University, Stellenbosch, South Africa , Grape and Wine Research Institute, Stellenbosch University, Stellenbosch, South Africa

Contact the author

Keywords

enzyme maceration, astringency, polysaccharide extraction, polyphenolic extraction, bitterness

Citation

Impact of high temperatures on phenolic profile of Babić grapes

Babić is a Croatian native grapevine variety grown in the Coastal region, mainly in the Šibenik and Primošten areas, famous for high quality red wines. The region is known for its warm Mediterranean climate and karst relief. Vineyards are found on the hillsides of varying slopes and exposition usually giving low yields of exceptional quality.

Using remote sensing to quantify the temporal and spatial effects of extreme weather events in vineyards

The increasing frequency of extreme weather events (EWE) represents a severe threat to viticulture.

How do different oak treatment affect the sensory composition of Chenin blanc wines over time?

Wooden barrels have been the preferred method for oak maturation for wines, but the use of alternative oak products, such as staves and oak chips have increased in South Africa due to lower production costs. This study investigated the effect of different oak products used during fermentation and ageing on the sensory profile, degree of liking and perceived quality of a South African Chenin blanc wine. The different wine treatments included an unoaked tank control wine, wines matured in 5th fill barrels, wines matured in new barrels from three different cooperages, and wines matured in 5th fill barrels with stave inserts from two different cooperages.

EFFECTS OF WINEMAKING FACTORS AND AGEING ON THE POLYPHENOLIC AND COLORIMETRIC PROFILES IN RED WINES PRONE TO COLOUR INSTABILITY

The effects of (A) grape freezing, and (B) malolactic fermentation, have been evaluated on the chemical and colorimetric profiles of red wines from Schiava grossa cv. grapes, thus prone to colour instability. The aim was to observe if specific variables (e.g. grape freezing) could improve the extraction and stability of pigments. The samples were studied from musts up to twelve months in bottle. The study was conducted with independent parallel micro-vinifications (12 = 4 theses x 3 replicates) under strictly-controlled conditions.

METHYL SALICYLATE: A TRENDY COMPOUND MARKER OF ZELEN, A UNIQUE SLOVENIAN VARIETY

The wine market interest for autochthonous varieties, particularly from less known wine regions, has significantly raised in the past few years. In that context, Slovenia, a small country from central Europe with a long winemaking tradition, is getting more and more attention, particularly through its range of unique regional varieties. Among them, Zelen, meaning “green” in Slovene, can only be found in the Vipava valley region, located on the western side of the country, near the border with Italy. When they are young, Zelen wines display very singular aromas reminiscent of rosemary, sage and white fruit. Despite its uniqueness, Zelen wine aromatic typicality is poorly documented in the literature.