The impact of global warming on modern oenological practice

A number of publications deal with the influence of global warming on the chemical composition and sensory properties of grapes and wines. High-temperature values shorten the time needed for grape harvesting. All parts of the berries cannot reach full ripeness and the sugar concentration in the grapes increases. The acidity of the grapes often decreases, which is accompanied by an undesirable increase in pH. All this leads to harvesting the grapes before the berries have reached their full technological maturity, which refers mainly to the skin and the seeds. The insufficient ripeness of the grapes affects the chemical composition and the quality of the wine. The wine does not have the required color intensity. With a long maceration, there is a risk of increased extraction of bitter tannins. In this situation, oenologists must apply the technological procedure used in conditions of in?completely ripened grapes, or wait for the grapes to fully ripen and then apply technological procedures to reduce alcohol content and pH. Thus, the variability of the climate from year to year affects the quality of the grapes and consequently the quality of the wine.