"Oenology" is the study of wines and winemaking. It does not include the study of vine-growing or grape-harvesting, which is called "viticulture". The English word "oenology" derives from the Ancient Greek word "oinos" meaning "wine" (οἶνος) and the suffix –"logia" meaning "study of" (-λογία).

Prior to the 19th century little was known about the process of fermentation or the causes of spoilage. In the mid-19th century, the French chemist Louis Pasteur and others explained the nature of fermentation and identified the yeasts responsible for it. Pasteur also identified the bacteria that spoil wine and devised a heating method (later called "pasteurization") to kill the bacteria. Later in the century, methods were developed for growing pure strains of specific yeasts in culture.

Advances in plant physiology and plant pathology also led to better vine training and less mildew damage to grapes. Stainless steel fermentation and storage tanks are easily cleaned and can be refrigerated to precise temperatures. Automated, enclosed racking and filtration systems reduce contact with bacteria in the air. Beginning in the 1960s, the use of mechanical grape harvesters and field crushers allowed quick harvesting and immediate transfer to fermentation tanks. Oenology includes these and many other elements of winemaking.

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