 IVES 9 IVES Conference Series 9 Impact of the pre-fermentative addition of enological adjuvants on the development of UTA in wines

Impact of the pre-fermentative addition of enological adjuvants on the development of UTA in wines

Abstract

AIM: During alcoholic fermentation and wine aging, indole-3-acetic acid (IAA) can degrade into 2-aminoacetophenone (AAP). The presence of reasonable amount of AAP in wines is regarded as the main cause of untypical ageing defect (UTA) described by aroma descriptors such as “acacia blossom”, “furniture polish”, “wet wool”, “mothball”, or “fusel alcohol” [1, 2]. This study aims to evaluate the effectiveness of different oenological adjuvants (ascorbic acid, glutathione, ellagic tannin, gallotannin and grape tannin) added to must in pre-fermentation for preventing the possible development of UTA. In addition, a high-resolution suspect-screening approach was performed to evaluate the kinetics of formation and consumption of metabolites formed during the oxidative degradation of IAA into AAP.

METHODS: Johannitter, Pinot Blank, Pinot Gris and Riesling musts were separately added with each of the 5 adjuvants (GrT, EgT, GaT, ASC and GSH), fermented and finally added of sulfur dioxide. The free and conjugated IAA forms were qualified or quantified in wine at the end of the fermentation and the AAP was finally quantified after a period of forced ageing (6 days at 40 °C). Quantification was performed using a HPLC coupled with a high-resolution mass spectrometer (UHPLC-HQOMS) using a biphenyl column (3×150 mm, 2.7 µm) with formic acid 2% and acetonitrile as eluents [3]. The quantification limits ranged from 0.25 to 2 μg/L, excepted for AAP that had a quantification limit of 0.02 μg/L. For qualitative analyses, homemade standards of indole-acetic acid-2-sulfonate (IAA-SO3H) and of metabolites produced by oxidative chemical reaction of IAA to AAP (radical cation, FAP, FAPOP and Ox-IAA) were prepared. The IAA-hexoside RT was studied with a full mass/all ion fragmentation/NL data dependent-MS2 (Full MS/AIF/NL dd-MS2) experiment in positive ion mode [4].

RESULTS: Ascorbic acid has been confirmed as the most appropriate antioxidant adjuvant which can be used for UTA defect prevention. With an almost comparable effect, gallotannin also did not show AAP productions greater than 1 µg/L. Over 80% of the variability of potential AAP formation in wines was explained by an ANCOVA model, which was used to predict the possible AAP production considering the varieties, treatments and IAA content in young wine as known variables.

CONCLUSIONS

Thanks to high resolution mass spectrometry, we were able to qualify and quantify different precursors and metabolites that take part in the development of UTA, allowing a better understanding of the mechanisms of AAP formation and the adjuvants actions involved in the wine protection.

DOI:

Publication date: September 14, 2021

Issue: Macrowine 2021

Type: Article

Authors

Tiziana Nardin

Technology Transfer Centre, Fondazione Edmund Mach, San Michele all’Adige, Italy,Tomas Roman, Susanne Dekker, Roberto Larcher Technology Transfer Centre, Fondazione Edmund Mach, San Michele all’Adige, Italy

Contact the author

Keywords

uta, AAP, HRMS

Citation

Old but gold: the interest for minor grapevine varieties – a case study in the Veneto region (Italy)

The biodiversity of cultivated vines has been significantly reduced due to a series of factors that have favoured the cultivation of a limited number of varieties and clones over time. In veneto, since 1980, a series of important actions have been implemented to counter this process. These actions have focused on the conservation of germplasm identified in the territory and the recovery of varieties historically present in the region, which were in danger of being abandoned and disappearing.

METABOLIC INTERACTIONS OF SACCHAROMYCES CEREVISIAE COCULTURES: A WAY TO EXTEND THE AROMA DIVERSITY OF CHARDONNAY WINE

Yeast co-inoculations in winemaking have been investigated in various applications, but most often in the context of modulating the aromatic profiles of wines. Our study aimed to characterize S. cerevisiae interactions and their impact on wine by taking an integrative approach. Three cocultures and corresponding pure cultures of S. cerevisiae were characterized according to their fermentative capacities, the chemical composition and aromatic profile of the associated Chardonnay wines. The various strains studied within the cocultures showed different behaviors regarding their development.

Identification of riboflavin low producer yeasts to prevent the light-struck taste in white wines

Wine quality maintenance during the storage is a fundamental aspect for both wine producers and consumers. Nowadays, great attention has been given to the light effect

Projected changes in vine phenology of two varieties with different thermal requirements cultivated in La Mancha DO (Spain) under climate change scenarios

The aim of this work was to analyze the phenology variability of Tempranillo and Chardonnay cultivars, related to the climatic characteristics in La Mancha Designation of Origin, and their potential changes under climate change scenarios. Phenological dates referred to budbreak, flowering, veraison and harvest were analyzed for the period 2000-2019. The weather conditions at daily time scale, recorded during the same period, were also evaluated. The thermal requirements to reach each of these phenological stages were calculated and expressed as the GDD accumulated from DOY=60. Changes in phenology were projected by 2050 and 2070 taking into account those values and the projected temperatures and precipitation, simulated under two Representative Concentration Pathway (RCP) scenarios –RCP4.5 and RCP8.5– using an ensemble of models. The average phenological dates during the period under study were, April 16th ± 6.6 days and April 5th ± 6.0 days for budbreak, May 31st ± 6.0 days and May 27th ± 5.3 days for flowering, July 26th ± 5.6 days and July 25th ± 5.8 days for veraison, and Ago 23rd ± 10.8 days and Ago 17th ± 9.0 days for harvest, respectively, for Tempranillo and Chardonnay. The projected changes in temperature imply an average change in the maximum growing season (April-August) temperatures of 1.2 and 1.9°C by 2050, and 1.6 and 2.6°C by 2070, under the RCP4.5 and RCP8.5 scenarios, respectively. A reduction in precipitation is predicted, which vary between 15% for 2050 under RCP4.5 scenario and up to 30% by 2070 under RCP8.5. The advance of the phenological dates for 2050, could be of 6, 7, 7, and 8 days for Tempranillo and 4, 6, 6 and 9 days for Chardonnay, respectively for budbreak, flowering, veraison and harvest under the RCP4.5 scenario. Under the RCP8.5 emission scenario, the advance could be up to 30% higher.

Comparison of the free radical-scavenging activity in infected oidium and sound dolcetto grape cultivar grown in a terroir of Central Italy

The importance of polyphenols, which are present in many vegetables and grapes too, is well-know and documented. Specific research works about the red grape