AIM: Different heat tests are used to predict a white wine haze risk after bottling. The most used tests are 30-60 min. at 80°C. Nevertheless, there is a lack of information about the relationship between the wine haze observed after such tests and the turbidities observed in the bottles after the storage/transport of the wines in more realistic Summer conditions (35-46°C during 3-12 days)

Climate change and rising atmospheric carbon dioxide concentration is a concern for agriculture, including viticulture. Studies on elevated carbon dioxide have already been on grapevines, mainly taking place in greenhouses using potted plants or using field grown vines under higher CO2 enrichment, i.e. >650 ppm. The VineyardFACE, located at Hochschule Geisenheim University, is an open field Free Air CO2 Enrichment (FACE) experimental set-up designed to study the effects of elevated carbon dioxide using field grown vines (Vitis vinifera L. cvs. Riesling and Cabernet Sauvignon). As the carbon dioxide fumigation started in 2014, the long term effects of elevated carbon dioxide treatment can be investigated on berry ripening parameters and fruit metabolic composition.
The present study aims to investigate the effect on fruit composition under a moderate increase (+20%; eCO2) of carbon dioxide concentration, as predicted for 2050 on both Riesling and Cabernet Sauvignon. Berry composition was determined for primary (sugars, organic acids, amino acids) and secondary metabolites (anthocyanins). Special focus was given on monitoring of berry diameter and ripening rates throughout three growing seasons. Compared to previous results of the early adaptative phase of the vines [1], our results show little effect of eCO2 treatment on primary metabolites composition in berries. However, total anthocyanins concentration in berry skin was lower for eCO2 treatment in 2020, although the ratio between anthocyanins derivatives did not differ.
[1] Wohlfahrt Y., Tittmann S., Schmidt D., Rauhut D., Honermeier B., Stoll M. (2020) The effect of elevated CO2 on berry development and bunch structure of Vitis vinifera L. cvs. Riesling and Cabernet Sauvignon. Applied Science Basel 10: 2486

he final concentration of phenolic compounds in the wines is usually lower than what might be expected given the phenolic concentration measured in grapes

A multi-element pedo-geochemical survey was carried out in Vrbničko polje vineyards on the Krk Island, Croatia. This Mediterranean winegrowing site is famous by Žlahtina wine production.

Red grapes contain significant amounts of phenolic compounds, known to contribute to wine quality and to provide important health benefits. Berry skin phenolics can be elicited by plant hormones. The aim of this work was to increase the content of anthocyanins and trans-resveratrol in five red varieties cultured in Argentina: Malbec (M), Bonarda (B), Syrah (S), Cabernet Sauvignon (CS), and Pinot Noir (PN), in two different growing regions: Santa Rosa (SR) and Valle de Uco (VU), by applying a post-veraison hormonal treatment with abscisic acid (ABA) and methyl jasmonate (MeJA).