IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Influence of Potential Alcohol and pH Adjustment on Polyphenols and Sensory Characteristics of Red Wines Produced at Different Harvest Time Points

Influence of Potential Alcohol and pH Adjustment on Polyphenols and Sensory Characteristics of Red Wines Produced at Different Harvest Time Points

Abstract

Wine quality is influenced by grape maturity, typically monitored by measuring sugar content and acidity. However, environmental factors such as extreme weather or fungal infections can force winemakers to harvest earlier than desired. This study investigated whether sugar and pH adjustment used to increase potential alcohol and reduce the perception of acidity, can also compensate for immaturity in terms of phenolic extractability, composition, and related sensory attributes. Since anthocyanin and sugar accumulation profiles do not necessarily run parallel during grape ripening, it was important to study several harvest time points.
Wines were made from Pinot noir and Cabernet Sauvignon grapes harvested in 2019 at three different stages of grape maturity, in the range of 18-24 Brix. After bottling, phenolic analysis (HPLC-DAD/FD, LC-QToF-MS and spectrophotometry) and sensory evaluation revealed that adjustment of early-harvest must to pH 3.3 and 24.5 Brix enhanced the extraction of seed-associated phenolics such as monomeric catechins, and resulted in higher ratings of a green, herbaceous and ethereal aroma, rough astringency and a harsh mouthfeel. Adjustment did not significantly increase concentrations of skin-associated phenolics such as anthocyanins and polymeric pigments, and could therefore not compensate for a lack of color intensity. Wines made from the late-harvest grapes had significantly higher concentrations of anthocyanins and polymeric pigments and lower concentrations of monomeric catechins and procyanidins. This resulted in wines with a full body and high ratings in color intensity, dark fruit aroma, and smooth astringency. The data suggests that anthocyanins and polymeric pigments can be used as markers for grape maturity. Potential alcohol and pH adjustment could not change the phenolic composition and sensory perception of an early-harvest wine to mimic those of a late-harvest wine.

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Article

Authors

Feifel Sandra1, Weilack Ingrid2, Wegmann-Herr Pascal3, Weber Fabian2 and Durner Dominik1

1Weincampus Neustadt, Institute for Viticulture and Oenology, Dienstleistungszentrum Ländlicher Raum (DLR) Rheinpfalz, Breitenweg 71, 67435 Neustadt an der Weinstraße, Germany
2University of Bonn (Germany)
3Institute for Viticulture and Oenology, Dienstleistungszentrum Ländlicher Raum (DLR) Rheinpfalz, Breitenweg 71, 67435 Neustadt an der Weinstraße, Germany

Contact the author

Keywords

List of different keywords (keyword1, keyword2, keyword3)

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Relationship between chemical parameters of tannins and in-mouth attributes of grape phenolic fractions

Establish relationships between taste and mouthfeel properties of grapes and tannin-related chemical parameters. Tempranillo Tinto and Garnacha Tinta grapes were harvested from distinct blocks in different dates; each sample collection date was separated by one week. Grapes were destemmed and macerated in 15% of ethanol for one week. The polyphenolic fraction (PF) of samples was submitted to solid phase extraction on C18 cartridges and recovered with ethanol. PFs were reconstituted in wine model and their taste and mouthfeel properties were characterised by rate-K-attributes methodology. In parallel, concentration (TC) and activity (TAc) of tannins as well as the concentration of tannins linked to anthocyanins (T-A) were determined using HPLC-UV–VIS.

Use of UHPH to improve the implantation of non-Saccharomyces yeasts

Ultra High-Pressure Homogenization (UHPH) is a high-pressure pumping at 300 MPa (>200 MPa) with a subsequent depressurization against a highly resistant valve made of tungsten carbide covered by ceramic materials or carbon nanoparticles. The intense impact and shear efforts produce the nano-fragmentation of colloidal biopolymers including the elimination of microorganism (pasteurization or sterilization depending on in-valve temperature) and the inactivation of enzymes.

Climate change, regional adaptation necessities and impact on grape and wine composition – an integrated view on a moving target

Grapevines are cultivated on 6 out of 7 continents, roughly between latitudes 4° and 56° in the Northern Hemisphere and between 6° and 42° in the Southern Hemisphere across a large diversity of climates (oceanic, warm oceanic, transition temperate, continental, cold continental, Mediterranean, subtropical, attenuated tropical, and arid climates).

Characterization of non-Saccharomyces yeast and its interaction with Saccharomyces cerevisiae with investigation of fermentation kinetics and aromatic composition

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.20.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Investigating the Ancient Egyptian wines: The wine jars database

In Ancient Egypt, wine was a luxury product consumed mainly by the upper classes and the royal family and offered to gods in daily religious rituals in the temples.
Since the Predynastic (4000-3100 BC) period, wine jars were placed in tombs as funerary offerings. From the Old Kingdom (2680-2160 BC) to the Greco-Roman (332 BC-395 AD) period, viticulture and winemaking scenes were depicted on the private tombs’ walls. During the New Kingdom (1539-1075 BC), wine jars were inscribed to indicate: vintage year, product, quality, provenance, property and winemaker’s name and title.