Technical Yearbook 2023

JUNE

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Minerality in wine – understanding the concept and factors involved By Karien O’Kennedy

This article will provide an overview of the current research on minerality in wine, highlighting the factors that influence it and the need for further investigation to understand its true nature. Wine is a complex beverage, and sensory experiences like minerality are often attributed to it, but the exact factors involved in creating such characteristics are not well understood. The term “minerality” is commonly used by wine critics and enthusiasts to describe a range of sensory experiences in wine, including earthy, flinty, stony, iodine, and salty flavours, among others. The scientific understanding of what causes these perceptions has been elusive. Minerality in wine refers to a perceived taste or aroma reminiscent of minerals or rocks, such as slate, flint, or wet stones. It is often associated with wines from cool climates and certain grape varieties, such as Chardonnay, Riesling, and Sauvignon blanc. It is typically described as a positive quality that adds complexity and depth to the wine. In the past, the most popular hypothesis for the origin of mineral character in wine was that it came directly from inorganic minerals in the vineyard soil. However, recent studies have shown that this is not the case.

So, what is causing the perception of minerality in wine? Researchers are still working to answer this question, but some promising findings have emerged. Sulphur compounds Research has indicated a link between minerality and low concentrations of sulphur-containing molecules. Some people, especially experts, perceive these low concentrations of reductive aromas as minerality. Studies have found a significant link between methanethiol and the chalky/shellfish aroma associated with minerality, often a characteristic of left-bank (of the Serein River) Chablis. Methanethiol also exerts a masking effect on fruity and floral notes, thereby enhancing the perception of minerality. Another study found that benzene methanethiol, also known as benzyl mercaptan or BMT, elicits flinty/smoky aromas when present in Sauvignon blanc. A statistical link was also found between BMT and the presence of flint and wet stone notes in Australian Chardonnay. Hydrogen disulphanes and trisulphanes are also linked to flinty aromas in dry white wines. These sulphur-containing molecules can be derived from microbiological or chemical reactions during winemaking and even after bottling. In contrast to all the findings from studies linking sulphur aromas to minerality, results from two studies could not find any relationship between volatile sulphur compounds

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TECHNICAL YEARBOOK 2023