Wine is a traditional alcoholic beverage deeply ingrained in human culture worldwide for millennia. It is a complex mixture of several hundred compounds, each playing an important role for its final quality. It consists of elements from grapes, products of yeast fermentation, and compounds that develop during extended maturation and aging. The two main ingredients of wine are water and ethanol, while other present components, such as sugars, acids, other alcohols and phenols contribute significantly to the formation of flavour, including sweetness and acidity, and colour of wine, despite their lower concentrations. While previous studies have been focused on determining the threshold concentrations of specific components that distinguish high-quality from lower-quality wine, the aim of my thesis research work was to investigate how concentrations of various components interact with each other and influence the final product. To achieve this, I employed Principal Component Analysis (PCA) to establish correlations between nine organic acids and eight inorganic anions. As part of my study, I developed a separation program using ion chromatography (IC) with conductivity detector. I analysed 105 wine samples, meticulously determining the concentrations of seventeen selected analytes. I performed PCA analyses based on various wine characteristics, such as variety, production region, sugar level, type and wine quality. I uncovered optimal grouping based on wine variety, which depends on the type of grape used, as well as the wine origin, which is influenced by soil composition and local weather conditions. Surprisingly, no significant grouping based on the type of wine (red/white/rosé) was detected. To improve future research, I propose determination of additional analytes. The discovered correlations between wine characteristics and selected analytes determination by ion chromatography represent the first step towards the long-term goal, i.e. the development of an artificial sommelier based on measured component concentrations in wine and machine learning.
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