This research investigated yeast populations and diversity during pre-fermentation cold maceration and alcoholic fermentation of Vitis vinifera L. cv. Pinot noir grapes from a commercial vineyard (Dayton, OR). Fermentations were conducted at the Oregon State University research winery in 100 L tanks while grapes from the same vineyard lot were...
One of the most common problems in wine production is the formation of hydrogen sulfide (H₂S) and other volatile sulfur compounds (VSCs), which can mask positive aromas at low concentrations and result in unpleasant aromas such as rotten egg, cabbage, garlic, and rubber at higher concentrations. Despite the large body...
Wine is particularly vulnerable to infection by Brettanomyces bruxellensis during or shortly after malolactic fermentation (MLF). While different methods and techniques enable winemakers to prevent wine spoilage due to this organism, no single intervention is universally sufficient. Moreover application of sulfur dioxide, the most commonly used of these methods, is...
The growth of Brettanomyces bruxellensis is a major cause of wine spoilage due tothe production of the volatile phenols 4-ethylphenol (4-EP) and 4-ethylguaiacol (4-EG), derivatives of p-coumaric acid and ferulic acid. During the winemaking process,some microorganisms can impact the concentration of the 4-EP precursors pcoumaricand coutaric acid (tartaric acid-esterified p-coumaric...