Organic acids in the form of nitrogen compounds. They are the basic building blocks for animal and vegetable proteins (Proteins) and elementary components of for example enzymes, Glutamines and vitamins, There are around 100 different forms, around 20 of which are also contained in the grape must. During the fermentation process they need yeasts certain amino acids for nitrogen supply during metabolism. You must take this from the must. If the soil is adequately supplied with nitrogen there is also a sufficient amount of amino acids in the must (about 1 g / l). The nitrogen content in the grapes is negatively influenced by Botrytis (Injury to the berry skin and leaching), lack of water, insufficient absorption of nitrogen via the roots and greening of the soil (competition for elemental nutrients).
A high degree of ripeness of the grapes has a positive influence on the nitrogen content. Because amino acids are strongly formed towards the end of ripening when the elemental nutrients are removed from the autumn leaves. Enzymatic decarboxylation results in biogenic amines from the amino acids. This is the most well-known made from histadine histamine, More are cadaverine. putrescine. spermidine. tryptamine and tyramine, Some of the histamine arises during the alcoholic period fermentation, in the malolactic fermentation as well as in higher concentration when stored in wooden barrels. In the autolysis (Yeast dissolution) desired aromatic amino acids are formed. The wine contains 1 to 4 g / l amino acids (see under total extract ). The taste sensation umami based on glutamic acid; one of the amino acids.