oenology

Oenology, also spelled œnology, is the science and study of wine and winemaking. It encompasses the chemical, physical, biological, and sensory aspects of wine production and quality control. In contrast to viticulture, which focuses on grape cultivation, oenology concerns the processes that transform grapes into wine, from fermentation to aging and packaging, and the evaluation of wine properties.

Winemaking involves several stages. Grapes are harvested, crushed and pressed to extract juice. Yeast converts sugars into ethanol and carbon dioxide during alcoholic fermentation, and conditions are managed to control temperature and flavor development. Malolactic fermentation may follow to soften acidity. The wine is clarified and stabilized, then aged in stainless steel or oak vessels before filtration and bottling.

Oenology integrates chemistry and microbiology. Key constituents include water, ethanol, organic acids (tartaric, malic, lactic), sugars, minerals, and a large suite of phenolic compounds that influence color, tannin structure, and mouthfeel. Aromatic compounds derived from grapes, fermentation, and aging define aroma and flavor. Yeast and bacteria drive fermentation; winemaking controls such factors as temperature, oxygen exposure, and nutrient availability to shape the final wine.

Sensory analysis and quality control are essential components. Wines are evaluated for aroma, flavor, balance, structure, and fault detection. Practical applications include quality assurance, flavor development, and compliance with labeling and geographic indications. Oenology continues to integrate advances in analytical chemistry, sensory science, and viticulture to improve consistency and understanding of wine.