In the context of climate change, excessive bitterness and astringency in wines have become increasingly prevalent. While variety selection and viticultural practices offer long-term solutions, they require considerable time before yielding practical results. In contrast, fining remains an accessible and immediate tool for winemakers.
Yeast cell wall components are valuable biotechnological tools with applications in oenology and beyond [1], [2].
The detection of reducing compounds such as phenolic acids, anthocyanins or tannins is of prime importance to decipher on the antioxidant and anti-aging properties of wines.
Bioprotection, leveraging beneficial microorganisms, has emerged as a sustainable approach to modern winemaking, minimizing reliance on chemical preservatives like as sulfur dioxide (SO₂).
During wine aging, small amounts of oxygen are absorbed and initiate a cascade of oxidation reactions. These aging reactions create many products including ethylidene-bridged oligomers and polymers of endogenous polyphenols, like flavan-3ols.
During aging, wine consumes small amounts of oxygen. This oxygen intake triggers a series of reactions that lead to flavonoid elongation, which is known to reduce bitterness and astringency while enhancing color stability.
Wine quality depends on grape biochemical constituents, including sugars, organic acids, amino acids, and bound and free aroma compounds, which are influenced by vineyard location and environmental factors such as temperature and precipitation [1].
Vinification trials were carried out between 2018 and 2021 in the experimental winery at Laimburg Research Centre, Alto Adige, to test the effect of grape stem inclusion during fermentation of Pinot Noir.
Resistant grape varieties are gaining interest in viticulture due to their resistance to diseases, allowing to drastically reduces pesticides in viticulture [1].
Reductive wine fault is characterized by the presence of odors such as rotten eggs or spoiled camembert cheese, originating from hydrogen sulfide (H2S) and methanethiol (MeSH) [1]. These compounds stabilize in polysulfide forms, creating a complex pool of precursors that will revert to both molecules when the environment becomes anoxic [2].
The valley of Caravelí (Peru) received the first vine plants in colonial times and the tradition of cultivation is maintained thanks to its terroir and artisanal techniques.
Table grapes (Vitis labrusca and hybrids) are widely cultivated in Brazil [1] due to the climate, their resistance to disease and the way they are consumed and commercialized, either in-natura or for processing, producing whole juices, jams and table wines.
Lipids are crucial in alcoholic fermentation, influencing yeast metabolism by providing nutrients and modulating membrane composition [1]. They also serve as precursors to aromatic compounds shaping wine sensory profiles [2].
It is widely known the impact that oxidation has on wine sensory degradation and eventually, in the shortening of its longevity.
Lactic acid bacteria (LAB) are essential microorganisms in winemaking due to their role in malolactic fermentation (MLF) [1]. This process not only ensures the biological stabilization of wine through the decarboxylation of malic acid into lactic acid but also contributes to modifications in the chemical composition of the wine [2][3].
Aging wine on lees benefits different wine sensory and technological properties including an enhanced resistance to oxidation. Several molecules released by yeast, such as membrane sterols and glutathione, have been previously proposed as key factors for this activity [1].
Structure-function relationships between the polysaccharide part of S. cerevisiae Mannoprotein Pools (MPs) and their potential to interact with anthocyanins and Protein-Tannins aggregates was previously assessed [1,2].
Press wines play a crucial role in red winemaking, representing up to 15% of the final blend [1]. Optimizing their value is essential both economically and for maintaining wine identity, especially given evolving climatic and societal challenges. However, little recent research exists on their composition.