Copper (Cu) is known to substantially impact wine stability through oxidative, reductive or colloidal phenomena. Recent work has shown that Cu exists predominantly in a sulfide-bound form, which may act as a potential source of sulfidic off-odours in wine and hence contribute to reductive flavours
PR proteins can cause haze in wines, and the risk is to keep the wine unsold. Generally, in winemaking bentonite solves this problem by removing proteins, but it is not a renewable resource, has poor settling, which means difficulty in filtering after use and a considerable loss of wine, it is not a specific adsorbent and may reduce aromas and flavor compounds
Œnococcus oeni is a wine-associated lactic acid bacterium performs the malolactic fermentation, which improves the taste and aromatic complexity of many wine.
During wine alcoholic fermentation, yeasts produce volatile aroma compounds from sugar and nitrogen metabolism. Some of the metabolic pathways leading to these compounds have been known for more than a century.
Nowadays the use of Torulaspora delbrueckii is more and more common in winemaking. However, its behavior in presence of Saccharomyces cerevisiae is not always predictable.