Use and impact of oxygen during winemaking

Abstract

It is generally acknowledged that oxygen can have both a positive and a negative impact on a wine's chemical composition and sensory attributes. During the production process, from the initial harvesting of grapes to maturation in bottle, there are numerous points at which oxygen can be introduced, either inadvertently or intentionally. The impact of oxygen on fermentative performance, as well as during maturation, has been the subject of extensive research, both during winery operations and in the final package. Recent studies have highlighted the impact of oxygen on wine chemistry during early parts of the winemaking process. This review will discuss the effect of oxygen introduction at various points, from harvest to completion of fermentation, of wine chemical composition. In reviewing the opportunities to modulate wine chemistry and stylistic outcomes through the control of oxygen exposure, the review will highlight critical knowledge gaps in the underlying science behind some processes that are common within the wine industry.

The Impact of Oxygen at Various Stages of Vinification on the Chemical Composition and the Antioxidant and Sensory Properties of White and Red Wines

“…Oxygen is essential for the synthesis of lipids, the proper composition of which in the yeast cell membrane affects the maintenance of the cell membrane's integrity, obtaining a high glycolysis index and the highest possible yield of ethanol production ( Table 2) [1,24]. The lack of oxygen at the Table 1: The influence of oxygen on the initial stages of vinification [1,[4][5][6][7].…”

“…In oxygen-free conditions, where lipid synthesis is impossible, the source of lipids is must [5]. Depending on the pressing and clarification techniques used, must may contain various amounts of phytosterols (β-sitosterol, campesterol, and stigmasterol) and fatty acids (palmitic, oleic, linoleic, and linolenic acids), which are essential for the growth and development of yeast [28].…”

“…These can be substitutes for ergosterol, and their use leads to an increase in yeast growth and fermentation activity. However, if no oxygen is added, these phytosterols can disrupt the proper membrane properties (these lipids replace the yeast-forming compounds and form the basis for membrane formation) and inhibit fermentation and its efficiency [5,29]. In order to prevent these phenomena, the fermenting must be oxygenated [27] and the time point of oxygen addition is also important.…”

“…Aldehydes are formed as a result of alcohol oxidation at the stage of fermentation and maturation of wines [1]. Table 2: The influence of oxygen during the fermentation stage [1,5,24,26,29].…”

“…The concentration of these compounds depends on the balance of alcohol acetyltransferase and esterase activity. These compounds cause the aroma of fruit, especially Sauvignon Blanc white wines, described in the literature as grapefruit aromas, guavas, and tropical fruits [5]. There are three mechanisms that cause these changes.…”