Grape seeds account for around 5% of the weight of the whole grape berry, representing approximately 40%-50% of the solid by-products that the different wine industries generate during the winemaking process.
In recent years, proteins endogenous to grape have become of great interest to the wine industry because they represent a new alternative to other biopolymers subjected to more legal restrictions (i.e. animal origin and synthetics) that can be used in technological applications to modulate sensory attributes such as wine color and have a positive impact on wine quality.
While the ethanol and tartaric acid contained in wine lees are typically recovered by distilleries, the remaining solid fraction (yeast biomass) is usually disposed of, thus negatively affecting the overall sustainability of the wine industry.
Among the macromolecules of enological interest in white wines, much attention has been paid to polysaccharides.
Climate change and reduction of inputs are two major challenges for viticulture and oenology. With increasing temperature, wines become less acid and microbiologically less stable (1).
Gewürztraminer is a well-known wine famous for its aroma profile, which is characterized by rose petals, cloves, lychees, and other tropical fruit notes.
Over the last decades, climate change and rising temperatures have impacted the wine industry. Wines from warm regions tend to have a higher pH and lower total acidity.
Aim: This work studies how successive O2 saturations affects the color and hydroxycinnamic
acids concentration in the absence and presence of laccase from B. cinerea with the aim of better understanding the browning processes.
Materials and methods: Grapes of Muscat of Alexandria were harvested and pressed with a vertical press to extract 60% of their juice. Aliquots of 30 mL of this must were placed in 60 mL flasks equipped with a pill (PreSens Precision Sensing GmbH) for measuring oxygen by luminescence (Nomasense TM O2 Trace Oxygen Analyzer).
Although oligosaccharides have much impact both on health (prevention of diabetes, cardiovascular disease), and on the perception of wine (sweetness, astringency, acidity or bitterness), information on their composition in wine is still limited.
The production of Port Wine requires the addition of grape spirit to stop the fermentation, ensuring the desired sweetness
Acidity is often touted as a predictor of wine ageability, though surprisingly few studies have systematically investigated the chemical basis for this claim.
The aromatic profile of a wine is the result of volatile molecules present in grapes (varietal or primary aromas) and those produced during the winemaking process of fermentation (secondary aromas) and during wine aging (tertiary aromas).
Chitin is the main structural component of a large number of organisms (i.e., mollusks, insects, crustaceans, fungi, algae), and marine invertebrates including crabs and shrimps.
(+)-Catechin—laccase oxidation dimeric standards were hemi-synthesized using laccase from Trametes versicolor in a water-ethanol solution at pH 3.6.
Pomace, stem, grapevine leaves, and vine shoots arise as so called winery by-products during the wine production process.
Oxygen plays a key role in the evolution of wine chemistry, within the non-volatile matrix. Polyphenol composition and structure, as well as the process of tannin polymerisation are directly impacted by oxidation, and this can occur during both fermentation and ageing.
Rhineland-Palatinate is Germany’s largest wine growing region. The recently launched collaborative project in the frame of the ‘Carl-Zeiss-Stiftungs-Kooperationsfonds für Nachhaltigkeitsforschung’ focusses on the risk-benefit assessment of the use of grape pomace (GP) from the region ‘Pfalz’ in Rhineland-Palatinate as a natural fertilizer
The valorization of winemaking byproducts is subordinated to the knowledge of their chemical characteristics. This work concerned the determination of the polyphenolic profile and the dietary fiber content of skins and seeds from unfermented and fermented pomace of different cultivars (Moscato bianco, Cortese, Arneis, Pinot Noir, Barbera, Grignolino, Nebbiolo), sampled from some wineries in the Piedmont area (Italy) during the 2020 harvest.