Keywords
Abstract
One of the most common types of crystalline haze of wines is the formation of crystals of tartaric salts in the finished products. Wine stability
after bottling is achieved by using modern diagnostic methods and technological approaches of processing wine materials. Crystalline haze of
wines is associated with the formation of potassium and calcium salts
of tartaric acid. Tartaric acid is the organic acid of wine that dissociates
into anions earlier than other acids. Thus, at pH 2,87, it breaks down into
the undissociated (molecular) form of tartaric acid (56,1% of its total
content), bitartrate (I stage of dissociation) – 41,7%, tartrate (II stage of
dissociation) – 2,2 %. At pH = 3,95, the ratio of forms is 6,5; 57,8; 35,7%,
respectively. Similar results of dissociation of malic acid at pH = 2,87
are 77,0; 22,8; 0,2% of its total content; at pH = 3,95 they are 20,0; 71,4;
8,6% of its concentration. At pH = 3,0, ratio of the molecular forms of
tartaric and malic acids is 0,68, dissociated according to I stage – 1,69; II
stage – 11,0. Study objective is to identify the relationship between the
cationic-anionic composition of wine materials and tendency to calcium
haze. Objects of the study are 64 samples of white table wine materials,
with the determined parameters of pH, temperature of saturation of calcium tartrate, content of tartaric acid, calcium (Ca2+), tartrate ions (Т2-). It
is shown that pH is an important characteristic of the tendency of wines
to crystalline calcium haze, since its values determine the degree of dissociation of tartaric acid. As a result of mathematical processing of the
experimental data, the relationship between the saturation temperature
(CaTar) and the ratios Т2-/Ca2+, tartaric acid / pH (coefficient of multiple
correlation r = 0,78) was revealed. The results of the study will be used
to improve the system of wine diagnostic tests in assessing the tendency
to calcium haze.