RU2802760C1 - Method for determining the resistance of white and rose wine materials to crystalline turbidity - Google Patents

Abstract

FIELD: winemaking.

SUBSTANCE: method for determining the resistance of white and pink wine materials to crystalline turbidity consists in quantitatively determining the mass concentrations of potassium cations, tartaric anions, the ratio of mass concentrations of potassium cations and tartaric acid anions (V₁), the volume fraction of ethyl alcohol (V₂), pH (V₃), mass concentrations of phenolic compounds (V₄), sugars (V₅), calculating the predicted percentage of precipitated potassium cations according to the formula, followed by recalculation of the percentage obtained into the mass concentration of precipitated potassium cations in mg/dm³ from the initial mass concentration of potassium cations and concluding as follows: when the content of precipitated potassium cations is less than 100 mg/dm³, the sample is stable; from 100 to 300 mg/dm³, processing of wine materials of medium intensity is necessary; above 300 mg/dm³, intensive processing is necessary.

EFFECT: acceleration and simplification of determining the resistance of wine to the formation of crystalline turbidity, increasing the reliability of the qualitative and quantitative determination of the formation of crystalline precipitates.

1 cl, 1 tbl, 3 ex

Description

The invention relates to the food industry and can be used in winemaking to control the quality of white and rose wine materials.

One of the main reasons for the violation of the stability of grape wines is the formation of crystalline turbidities, most of which are potassium salts and tartaric acid [Gnilomedova N.V. Anikina N.S., Chervyak S.N. Destabilization of wines. Crystal formation of potassium salts // “Magarach”. Viticulture and winemaking, 2019, 3(109). P. 261-266].

Currently available methods for monitoring and predicting the stability of wines to crystal haze are divided into:

- calculated - based on mathematical models of wine behavior, depending on its composition;

- provocative - based on the creation of conditions that accelerate the formation of crystalline opacities;

- instrumental - based on the measurement of individual parameters of the wine, characterizing its tendency to crystalline cloudiness.

There is a known method for determining the resistance of wine materials to crystalline turbidity by the absolute concentration of potassium cations [Ageeva N.M. Stabilization of grape wines: theoretical aspects and practical recommendations. Krasnodar: SKZNIISiV Rosselkhozakademii, 2007, 251 p.], in which the mass concentration of potassium cations in wine material is determined and this indicator is assessed, the sample is considered stable if the content of potassium cations does not exceed 400 and 600 mg/dm ³ for table and liqueur wines respectively.

There is a known method for determining the resistance of wine materials to crystalline turbidity by the absolute concentration of potassium cations [Valuiko G.G., Zinchenko V.I., Mekhuzla N.A. Stabilization of grape wines / Ed. Valuiko G.G. Simferopol: Tavrida, 2002. 207 p], in which the mass concentration of potassium cations in wine material is determined and this indicator is assessed, the sample is considered stable if the content of potassium cations does not exceed 450 mg/dm ³ .

The disadvantages of these methods are:

- lack of quantitative characteristics of precipitated potassium;

- failure to take into account all parameters that influence crystal formation processes.

There is a known method for determining the resistance of wine to crystalline turbidity (RF Patent No. 2304768, G01N 33/14, publ. 08.20.2007, Bulletin No. 23), which involves taking a sample, introducing an electrolyte into it, establishing the presence of colloidal particles and judging the resistance to turbidity , while in the sample before the introduction of the electrolyte, the initial concentration of colloidal particles N ₀ is measured and 10-12 minutes after the introduction of the electrolyte - their final concentration N _to , after which the coefficient of the relative decrease in the concentration of colloidal particles after the introduction of the electrolyte is determined Y = {(N ₀ - N _to )/N ₀ }⋅100%, the forecast of wine resistance to crystalline haze is carried out by exceeding the coefficient value equal to 15%.

The disadvantage of this method is the need to perform specific analyzes on equipment that is not typical for wine production.

There is a known method for predicting the resistance of wine materials to crystalline turbidity [Berg H.W., Keefer R.M. Analytical determination of tartrate stability in wine. Am. J. Enol. Vitic, 1959 (10) 3: 105-109], in which the volume fraction of ethyl alcohol, pH, mass concentration of potassium cations and tartaric acid, forms of tartaric acid anions depending on pH are determined in the wine material under study and compared with the formula developed with using water-based model solutions:

where: SP(KNTar) is the concentration of the product in the form of potassium bitartrate, mol/dm ³ ; C(K+) - concentration of potassium ions, mol/dm ³ ; C(VK) - concentration of tartaric acid, mol/dm ³ ; w (НТar-) – fraction of bitartrate ion, calculated from tabular data, %. The data obtained are compared with previously accumulated long-term studies of the corresponding type of wine and a conclusion is drawn about its potential instability.

The disadvantages of this method are:

- the need for a significant database, unique for each terroir, variety and method of production;

- the development of the method was based on water-based model solutions, which do not take into account the multicomponent composition of wine;

- failure to take into account the influence of the mass concentration of phenolic substances and sugars, which can significantly accelerate or slow down the processes of crystal formation and sedimentation;

- the method does not have a quantitative characteristic of precipitated potassium.

There is a known method for determining the resistance of wine materials to crystalline turbidity [Pavlenko N.M., Ogorodnik S.T., Rudyshina N.M. Methods for controlling cold treatment. Modern methods of regulating technological processes of winemaking // Sat. scientific tr. VNIIViPP "Magarach". T. XXIII. Yalta, 1986. P. 94-105.], in which the volume fraction of ethyl alcohol, pH, mass concentration of potassium cations and tartaric acid are determined in the wine material under study and calculated according to developed nomograms and tables of the solubility product of potassium bitartrate for the corresponding wine storage temperature. The theoretical concentration of potassium (C _K , g/dm ³ ) is calculated using the formula:

where: PR is the product of the solubility of potassium bitartrate; C _VC - mass concentration of tartaric acid, g/dm ³ ; k - correction factor. The value of C _K is compared with the actual potassium content. Wine material is considered stable to crystal formation if the actual potassium concentration does not exceed the calculated one.

The disadvantages of this method are:

- failure to take into account the influence of the mass concentration of phenolic substances and sugars, which can significantly accelerate or slow down the processes of crystal formation and sedimentation;

- the difference in storage conditions of wine materials before bottling and wine in bottles is not taken into account when determining the solubility of potassium bitartrate;

- the duration of obtaining the result due to the need to work with a large array of tables and nomograms;

- lack of quantitative characteristics of precipitated potassium.

The technical result of the invention is to speed up and simplify the determination of the resistance of wine to the formation of crystalline hazes, to increase the reliability of the qualitative and quantitative determination of the formation of crystalline sediments, on the basis of which the need for additional treatments of the wine material is predicted to ensure the stability of the wine to crystalline hazes after bottling.

The process of formation of crystalline opacities is a simple process of the formation of salts of poorly soluble weak electrolytes, however, the process can be accelerated or slowed down by the physicochemical parameters of the solution. Since wine is an extremely complex multicomponent system, predicting the course of crystal formation in it is difficult. To reliably predict the formation of sediments and optimize methods for dealing with them when developing the method, the main physical and chemical parameters of wine materials were analyzed (by generally known methods), which influence the stability of wines to crystalline turbidity. Moreover, these indicators are usually controlled during wine production. As a result of research and statistical processing of data from them, statistically significant indicators were identified: mass concentration of potassium cations, tartaric acid anions, ratio of mass concentrations of potassium cations and tartaric acid anions, volume fraction of ethyl alcohol, pH, mass concentrations of phenolic compounds, sugars. With the help of correlation-regression data analysis, using the piecewise linear regression module with break points at the first stage, the distribution functions of the indicators were established. The subsequent construction of a mathematical model was carried out using regression specified by the user, as a result of which the Statistica 6 program obtained a formula with parameters describing the crystal formation process with calculation of the proportion of precipitated potassium cations, i.e. Potentially possible crystalline precipitation during violation of wine storage and transportation conditions.

Thus, the technical result of the proposed invention is achieved by determining the mass concentrations of potassium cations, tartaric acid anions, the ratio of the mass concentrations of potassium cations and tartaric acid anions (V ₁ ), the volume fraction of ethyl alcohol (V ₂ ), pH (V ₃ ), mass concentrations phenolic compounds (V ₄ ), sugars (V ₅ ), are calculated using the formula for the predicted percentage of precipitated potassium cations:

followed by recalculation of the resulting percentage into the mass concentration of precipitated potassium cations in mg/dm ³ from the initial mass concentration of potassium cations. When the amount of precipitated potassium cations is less than 100 mg/dm ³ the sample is stable, from 100 to 300 mg/dm ³ - medium-intensity processing of wine materials is necessary, above 300 mg/dm ³ - intensive processing.

The determination of wine resistance to the formation of crystalline hazes is accelerated and simplified, since the indicators determined for the calculation are basic and are determined at all enterprises as part of technological control, which eliminates the need for unnecessary analyzes and the use of specific equipment.

Testing of the developed method for predicting the formation of crystalline turbidity in wine materials revealed that it is reliable for white and rose wine materials; the prediction error does not exceed 15%. Red wine materials have a more complex composition of phenolic compounds, which also affect the formation of sediments, so this method has a prediction error of more than 15% and is less significant.

Examples of specific implementation.

Example 1. In a sample of dry white wine material Chardonnay, physicochemical parameters were determined (Table): mass concentration of potassium cations, tartaric acid anions, ratio of mass concentration of potassium cations and tartaric acid anions (V ₁ ), volume fraction of ethyl alcohol (V ₂ ), pH (V ₃ ), mass concentration of phenolic compounds (V ₄ ), sugars (V5), and the predicted percentage of precipitated potassium cations was calculated using the formula:

The percentage of precipitated potassium cations was 32.77% of the initial mass concentration. Thus, with an initial mass concentration of potassium cations (before treatment) of 1330 mg/dm ³ , the predicted mass concentration of potassium cations will be 436 mg/dm ³ , which interact with tartaric acid anions to form precipitation. The sample is not stable and requires intensive processing to stabilize it against crystalline opacities. Thanks to the obtained forecast, longer processing modes are selected depending on the available equipment.

To confirm the reliability of the results, the wine material was placed in conditions that provoked crystalline precipitation, the mass concentration of potassium cations was determined and the actual percentage of precipitated potassium cations was calculated, the prediction error in this example was 14.85% (Table).

Example 2. In a sample of sweet white wine material Muscat, similar to example 1, the physicochemical parameters were determined (Table), the predicted percentage of precipitated potassium cations was calculated using the formula, which amounted to 50.86% of the initial mass concentration (750 mg/dm ³ ), therefore, up to 381 mg/dm ³ of calcium cations interact with tartaric acid anions to form precipitation.

The sample is not stable and requires intensive processing to stabilize it against crystalline opacities. Thanks to the obtained forecast, longer processing modes are selected depending on the available equipment.

The error of the forecast in comparison with the actual ones in this example was 10.35% (Table).

Example 3. In a sample of dry rose wine material Cabernet Sauvignon, similar to example 1, the physicochemical parameters were determined (Table), the predicted percentage of precipitated potassium cations was calculated using the formula, which amounted to 36.25% of the initial mass concentration (742 mg/dm ³ ), therefore , up to 269 mg/dm ³ of calcium cations interact with tartaric acid anions to form precipitation.

The sample is not stable; medium-intensity treatment is required to stabilize it against crystalline opacities. Thanks to the obtained forecast, moderate processing modes are selected depending on the available equipment.

The forecast error in comparison with the actual ones in this example was 11.13% (Table).

Example 4. In a sample of sweet white wine material Sauvignon Blanc, similar to example 1, the physicochemical parameters were determined (Table), the predicted percentage of precipitated potassium cations was calculated using the formula, which amounted to 26.97% of the initial mass concentration (362 mg/dm ³ ), therefore , up to 98 mg/dm ³ of calcium cations interact with tartaric acid anions to form precipitation. The sample is stable; to process it, it is enough to filter it before bottling with the addition of metatartaric acid.

The forecast error in comparison with the actual ones in this example was 14.74% (Table).

After treatments of the recommended intensity, all wine materials were stable to crystalline turbidity; when storing wine for a month after bottling in violation of storage conditions (at low and high temperatures), no precipitation was detected; this is enough to confirm the reliability of the method and the sufficiency of quantitative determination of the formation of crystalline clouds. sediments in order to optimize methods of dealing with them and ensuring the stability of wine against crystalline clouding after bottling.

Thus, this method takes into account indicators that are guaranteed to be involved in the formation of crystalline opacities, allowing one to quickly predict the quantitative characteristics of precipitated potassium. The obtained result makes it possible to determine the intensity of further processing of the wine material in order to stabilize it to crystalline turbidity, while there is no need for complex analyzes; the method is unified regardless of the region of wine production, variety and production method.

Claims (3)

A method for determining the resistance of white and pink wine materials to crystalline opacities, which consists in quantitatively determining the physical and chemical parameters of the wine material, characterized in that the mass concentrations of potassium cations, tartaric acid anions, the ratio of the mass concentrations of potassium cations and tartaric acid anions (V ₁ ), volumetric the proportion of ethyl alcohol (V ₂ ), pH (V ₃ ), mass concentrations of phenolic compounds (V ₄ ), sugars (V ₅ ), are calculated using the formula predicted percentage of precipitated potassium cations: followed by recalculation of the resulting percentage into the mass concentration of precipitated potassium cations in mg/dm ³ from the initial mass concentration of potassium cations and the conclusion: when the content of precipitated potassium cations is less than 100 mg/dm ³ , the sample is stable, from 100 to 300 mg/dm ³ - treatment is necessary wine materials of medium intensity, above 300 mg/dm ³ - intensive processing.