 IVES 9 IVES Conference Series 9 Proanthocyanin composition in new varieties from monastrell

Proanthocyanin composition in new varieties from monastrell

Abstract

AIM: Proanthocyanidins are responsible in an important way for positive aspects in wines, such as body and color stability in red wines, but they are also responsible for sensory characteristics that can be negative for their quality when found in excessive concentrations. In an effort of increasing our understanding of crosses from Monastrell, it has been studied their proanthocyanidin composition during three seasons. Besides, it is important the idea of registering new varieties of red grapes from Monastrell adapted to the new climatic scenario produced in the South East of Spain, with an excellent polyphenolic capacity.

METHODS: A quantitative analysis was carried out during three seasons (2018, 2019 and 2020) in order to study and compare the obtained concentration of proanthocyanidins in Monastrell and the new varieties MC80 (Monastrell x Cabernet-Sauvignon), MC98, MS10 (Monastrell x Syrah), MC4 and MC18. The analysis was carried out in grapes as well as in the final of alcoholic fermentation in order to study its extraction capacity. The analyzes were performed and quantified following the fluoroglycinolysis method.

RESULTS: In general, the results showed higher concentrations in tannins in the most hybrids of Monastrell for the three seasons studied.Furthermore, a higher concentration of epigallocatechin was found in most of the hybrid wines elaborated, being positive from an organoleptic point of view, since this compound provides softness to the wines. However, MC4 is characterized by its low concentration of this compound although these values could be normal since the concentration of tannins in this variety is much lower with respect to the other hybrids. Another of the compounds of interest analyzed was epicatequinogalate, this compound was also found in higher concentrations in hybrids analysed than in Monastrell variety.Finally, It should be noted that the relationship between the average degree of polymerization of the tannins and the percentage of gallolation was much higher in the seeds than in the elaborated wines or in the skins.

CONCLUSIONS

These new varieties ensuring its incredible polyphenolic concentration showing a great potential as new varieties adapted to the dry and hot conditions produced in the south east of Spain

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

J.D, Moreno-Olivares

Murcian Institute of Agricultural and Food Research and Development (IMIDA). C/ Mayor s/n 20150, La Alberca (Murcia).,M.J, Giménez-Bañón D.F, Paladines-Quezada J.C, Gómez-Martínez A, Cebrían-Pérez J.I, Fernández-Fernández J.A, Bleda-Sánchez R, Gil-Muñoz Murcian Institute of Agricultural and Food Research and Development (IMIDA). C/ Mayor s/n 20150, La Alberca (Murcia).

Contact the author

Keywords

tannins, polyphenolic composition, Vitis vinifera, crosses, cromatography

Citation

Impact of glutathione and elemental sulphur juice addition on the volatile thiol production in South African Sauvignon blanc wine

Three compounds, 3-mercaptohexanol (3MH), 3-mercaptohexyl-acetate (3MHA) and 4-mercapto-4-methylpentan-2-one (4MMP), also known as varietal thiols, have been identified to contribute positively to wine aroma and are responsible for the distinct gooseberry, grapefruit, guava and box tree character found in Sauvignon blanc wines. Certain volatile thiol compounds though, can cause off-aromas of onion, garlic, rubber and rotten egg, this group of molecules is known as reductive sulphur compounds (RSC). This study looks into how the addition of sulphur-compounds to Sauvignon blanc juice contributes to the varietal thiol (3MH and 3MHA) concentration and reductive sulphur compound concentration in South African Sauvignon blanc wine.

The interplay between grape ripening and weather anomalies – A modeling exercise

Current climate change is increasing inter- and intra-annual variability in atmospheric conditions leading to grapevine phenological shifts as well altered grape ripening and composition at ripeness. This study aims to (i) detect weather anomalies within a long-term time series, (ii) model grape ripening revealing altered traits in time to target specific ripeness thresholds for four Vitis vinifera cultivars, and (iii) establish empirical relationships between ripening and weather anomalies with forecasting purposes. The Day of the Year (DOY) to reach specific grape ripeness targets was determined from time series of sugar concentrations, total acidity and pH collected from a private company in the period 2009-2021 in North-Eastern Italy. Non-linear models for the DOY to reach the specified ripeness thresholds were assessed for model efficiency (EF) and error of prediction (RMSE) in four grapevine cultivars (Merlot, Cabernet Sauvignon, Glera and Garganega). For each vintage and cultivar, advances or delays in DOY to target specified ripeness thresholds were assessed with respect to the average ripening dynamics. Long-term meteorological series monitored at ground weather station by means of hourly air temperature and rainfall data were analyzed. Climate statistics were obtained and for each time period (month, bimester, quarter and year) weather anomalies were identified. A linear regression analysis was performed to assess a possible correlation that may exist between ripening and weather anomalies. For each cultivar, ripeness advances or delays expressed in number of days to target the specific ripening threshold were assessed in relation to registered weather anomalies and the specific reference time period in the vintage. Precipitation of the warmest month and spring quarter are key to understanding the effect of climate change on sugar ripeness. Minimum temperatures of May-June bimester and maximum temperatures of spring quarter best correlate with altered total acidity evolution and pH increment during the ripening process, respectively.

Ethanol reduces grapevine water consumption by limiting transpiration

Studies suggest that ethanol (EtOH), triggers plant adaptation to various stresses at low concentrations (10 µM to 10 mM).

Climatic influences on Mencía grapevine phenology and grape composition for Amandi (Ribeira Sacra, Spain)

During the year 2009 we have studied the phenology and grape composition of Mencía cultivar in seven different situations (orientation and altitude) for Amandi subzone

Under trellis cover crop induces grapevine tolerance to bunch rot

Botrytis bunch rot occurrence is one of the most important limitations for the wine industry in humid environments. A positive correlation between grapevine growth and susceptibility to fungal pathogens has been found. In theory the effect of grapevine vegetative growth on bunch rot expression results from direct effects (cluster architecture, nitrogen status among others) and indirect ones (via microclimate). However, a reduction in bunch rot incidence can be achieved in some circumstances without major vine growth reduction. The present study was aimed to test the general hypothesis that bunch rot susceptibility is affected by vine vigor, but other factors associated with grapevine vegetative expression could be even more relevant.