10.22184/2227-572X.2025.15.3.210.221

A rapid method for determining the sugar content and alcohol content of grape wines with-out preliminary distillation of ethyl alcohol is proposed. The method is based on measuring the refractive index and density of the sample and using the additivity principle of refracto-­densimetric characteristics – the refraction intercept and specific refraction. The method can be used in laboratory conditions, and in the presence of pairs of immersion or flow refractometers and densimeters (densitometers) built into process tanks or product pipelines, it can be implemented in production. The method considers wines as pseudo­ternary mixtures of aqueous solutions of sugars (fructose : glucose 1 : 1), ethanol and organic acids (tartaric : malic 3 : 1 wt.). Other minor components of wines, close in refracto-­densimetric characteristics to the acid benchmark, also implicitly contribute to the last component. The method has no concentration restrictions on the components to be determined. The trajectories of the fermentation process of sugar and grape must are shown on the Kurtz-­Lorentz chemographic map. A simplified version of the method considers wines as binary mixtures of aqueous solutions of sugars and ethyl alcohol, in which case the composition of wines can be deter­mined graphically using the Kurtz-­Lorentz nomogram or calculated using a similar algorithm. The results of measuring wine samples show good agreement between certain composition indicators and those declared by producers.