# The Use of Machine Learning for Comparative Analysis of
## 2 Materials and Methods  
The materials for this study were young single-grade white and red table wine materials produced under conditions of the Black Sea region: \"Aligote\", \"Cabernet Sauvignon\", \"Merlot\", \"Riesling of the Rhine\", \"Rkatstieli\", \"Bastardo Magarachsky\", and varietal sherry wine material. We used gallic acid, quercetin (Fluka Chemie AG, Switzerland), and Trolox-C (Sigma-Aldrich, Switzerland) as reagents. The antioxidant activity was determined using the amperometric method in the analyzer of the antioxidant activity of substances Tsvet YAUZA-01-AA. For this, the method No. 00334830-055-2008, approved by the Institute of viticulture and winemaking \"Magarach\", was used. To determine AOA by the chemiluminescent method, a Photochem (Analytik Jena AG) [12; 18] instrument was used. Method No. 00334830-075-2010, approved by the Institute of viticulture and winemaking \"Magarach\", was used. These guidelines describe all of the necessary conditions and standards (basic preparations, reagents used, concentration of reagents, time and development of the analysis, etc.). In our subsequent publications, we intend to describe these techniques in detail. The range of determination of antioxidant activity by the chemiluminescent method is from 5 \(\mu\)mol/dm\({}^{3}\) to 2 mol/dm\({}^{3}\) in terms of the Trolox-C standard. The content of water-soluble antioxidants was determined by the amperometric method in the range from 0.2 to 4.0 mg/dm\({}^{3}\) inclusive (Table 1). The amperometric method for determining antioxidant activity is most widely used in the CIS countries, while the chemiluminescent method, which is a fast and highly accurate method for determining antioxidant activity, is widely used in Europe. The mass concentration of phenolic substances was determined by the photocolorimetric method on a Unico 1200 spectrophotometer manufactured by United products and instruments (USA) [13; 14]. A schematic description of the research process of comparative analysis of methods for determining antioxidant activity and determining the phenolic profile of wines is presented in Figure 1.  
To assess the potential ability of wines to exhibit AOA, it is important to determine the mass concentration of the sum of phenolic substances. \begin{table}
\begin{tabular}{c c c} \hline \hline \(\boldsymbol{\mathsf{N}}\) & **The Methods for Determining** & **The Measurement Range** \\  & **Antiv oxidant Activity** & **The Measurement Range** \\ \hline
1 & The chemiluminescent method & 5 \(\mu\)mol/dm\({}^{3}\)-2 mol/dm\({}^{3}\) \\
2 & The amperometric method & 0.2–4.0 mg/dm\({}^{3}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The methods for determining antioxidant activity and their limits of detection. Figure 1: Correlation of amperometric and chemiluminescent methods to determine the AOA of white and red table wine materials. method to determine the mass concentration of phenolic substances is based on measuring the number of phenolic substances by changing their color during oxidation with the Folin-Ciocalteu reagent, consisting of a mixture of phosphoric-tungsten H\({}_{3}\)PW\({}_{12}\)0\({}_{40}\) and phosphoric-molybdenum H\({}_{3}\)PMo\({}_{12}\)O\({}_{40}\) acids, which are reduced by the oxidation of phenols into a mixture of tungsten oxides (W\({}_{8}\)O\({}_{23}\)) and molybdenum (MoSO\({}_{23}\)) of the blue color [13; 19]. The determination is carried out in an alkaline medium, at a wavelength of 765 nm. Qualitative and quantitative analysis of the phenolic composition of the analyzed wines was determined by HPLC using an Agilent Technologies chromatographic system (model 1100) with a diode array detector. To separate substances, a Zorbax SB-C18 chromatographic column with a size of 2.1-150 mm was used, filled with silica gel with a grafted octadecylsilyl phase with a sorbent particle size of 3.5 \(\upmu\)m. Chromatography was carried out in a gradient mode. Fluent composition: solution A--methanol, solution B--0.6% aqueous solution of trifluoroacetic acid.