terclim by ICS banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2023 9 Identifying best parameters to characterize genotypes capability of retaining adequate malic acid at harvest and in final wines

Identifying best parameters to characterize genotypes capability of retaining adequate malic acid at harvest and in final wines

Introduction

Under current climate change pressures, obtaining grapes with adequate acidity at harvest is one of the main challenges for growers, especially if the goal is producing sparkling wines. This issue arises from two main occurrences: i) higher temperatures enhance degradation of malic acid; ii) grape maturity may occur under suboptimal climatic conditions due to an advanced phenology (Palliotti et al. 2014). For this reason, the introduction of new varieties or the reconsideration of minor and insofar neglected cultivars or clones are gaining enormous interest and popularity (Palliotti et al. 2014, Poni et al. 2020, Antolìn et al. 2020). However, criteria for the identification of performing genotypes in terms of ‘acidity at harvest’ are complex. Late veraison and ripening can be inappropriate traits, since they do not necessarily mean that grapes maintain adequate acidity in relation to a satisfying sugars concentration (Palliotti et al. 2014, Frioni et al. 2020). Considering the evolution and the destination of organic acids in grapes, pre-veraison malic acid pool could represent a promising trait. In the same framework, an eventual genetic control over malic acid degradation rates could lead to different conclusions. The same can be said for the ratio between minimum acidity and starting malate abundancy, or for sugars/acidity ratio. However, any of the above-mentioned parameters seems to underestimate some of the factors involved, or in any case to provide an incomplete overview of grapes ripening.

DOI:

Publication date: June 20, 2023

Issue: GiESCO 2023

Type: Article

Authors

Tommaso FRIONI1*, Riccardo COLLIVASONE1, Silvia PAGANI1, Ginevra CANAVERA1, Matteo GATTI1, Mario GABRIELLI2, Stefano PONI1

1Dept. Of Sustainable Crop Production, Università Cattolica del Sacro Cuore, Piacenza, PC, Italy
2Dept. Of Sustainable Food Processing, Università Cattolica del Sacro Cuore, Piacenza, PC, Italy

Contact the author*

Keywords

acidity, malic acid, phenotyping, germoplasm, wine quality

Tags

GiESCO | GIESCO 2023 | IVES Conference Series

Citation

Related articles…

An excessive leaf-fruit ratio reduces the yeast assimilable nitrogen in the must

Yeast assimilable nitrogen (YAN) in the grape must is a key variable for wine quality as a source of aroma precursors. In a situation of YAN deficiency, a foliar urea application upon the vine at veraison enhances YAN concentration and facilitates must fermentation. In 2013, Agroscope investigated the impact of leaf-fruit ratio on the nitrogen (N) assimilation and partitioning in grapevine Vitis vinifera cv. Chasselas following foliar-urea application with the aim of improving its efficiency on the YAN concentration.

Extraction of polyphenols from grape marc by supercritical fluid extraction (SFE) and evaluation of their ‘bioavailability’ as dietary supplements

In the winemaking process, several compounds that remain in the grape skins and seeds after the fermentation stage are bioactive-compounds (substances with potential beneficial effects on health) that can be extracted in order to recovery valuable substances with a high commercial value for the cosmetic, food (nutraceuticals) and pharmaceutical industries. The skins contain significant amounts of bioactive substances such as tannins (16-27%) and other polyphenolic compounds (2-6.5%) in particular, catechins, anthocyanins, proanthocyanins, quercetin , ellagic acid and resveratrol.

The impacts of frozen material-other-than-grapes (MOG) on aroma compounds of red wine varieties

An undesirable note called “floral taint” has been observed in red wines by winemakers in the Niagara region caused by large volumes of frozen leaves and petioles [materials-other-than-grapes (MOG)] introduced during mechanical harvest and subsequent winemaking late in the season. The volatiles, which we hypothesized are responsible, are primarily terpenes, norisoprenoids, and specific esters in frozen leaves and petioles. The purpose of this study was to investigate the volatile compounds which may cause the floral taint problem and explore how much of them (thresholds) may lead to the problem. Also, the glycosidic precursors of some of these compounds were analyzed to see the changes happening during frost events.

Aromatic profile of six different clones of Chardonnay grape berries in Minas Gerais (Brazil)

Aromas are one of the key points in food analysis since they are related to character, quality and consequently consumer acceptance. It is not different in the winery industry, where the aromatic profile is a combination of viticultural and oenological practices. Based on the development of more aromatic clones and on the potential to produce sparkling wines at Caldas, in the southern region of Minas Gerais (Brazil) (21°55´S and 46°23´W, altitude 1,100m), the aim of this work was the determination of volatile compounds in six different clones of Chardonnay grape berries to better understand which compounds add bouquet to the wine, and additionally comprehend the impacts of the edaphoclimatic and annual conditions on the improvement of grape-growing and winemaking practices.

Improving stilbenes in vitis Labrusca L. Grapes through methyl jasmonate applications

Grapes (Vitis sp.) are considered a major source of phenolic compounds such as flavonols, anthocyanins and stilbenes. Studies related to the beneficial effects of these compounds on health have encouraged research aimed at increasing their concentration in fruits. On this behalf, several plant growth regulators such as jasmonic acid and its volatile ester, methyl-jasmonate (MeJa), have demonstrated promising results in many fruits. However, Brazilian subtropical climate might interfere on treatment response. The present study aims to evaluate the application of MeJa in the pre-harvest period in Concord and Isabel Precoce grapes (Vitis labrusca L.).