The grapes - Enozentrum
They are sweet, more or less acidic and come in a variety of shapes and colours. They can be spherical, elliptical, ovoid, cylindrical ... Bluish, reddish, pinkish, yellowish, more golden, darker or lighter...
If you look at a grape berry, you can only see its outer layer, what is known as the skin. The fine skin covering the grape berry contains most of the compounds that give each variety, and therefore each type of wine, its own personality. Thus, with a water content of between 72-80%, it also contains anthocyanins that give the red grapes their colour; tannins that provide structure; and aroma precursor substances. From a winemakers point of view, this is the most important part of the grape.
If you very carefully remove the skin, this will reveal the pulp holding the seeds. The pulp is primarily made up of water (65-80%) and sugars which will be converted into alcohol during the fermentation process. Furthermore, it contains organic acids, such as tartaric, malic and citric acid, necessary for the subsequent conservation of the wine and to give it freshness.