The influence of external factors on the alcoholic fermentation of wine yeasts

The sensory properties of a wine depends on its colours, aromas and flavors. Regarding red wines, the gustatory part consists of the acid, bitter and sweet tastes

Winemaking grapes contain a diverse array of non-volatile precursors that become noticeable only after hydrolysis reactions or molecular rearrangements, during which aroma compounds are generated and released [1]. Among these, glycosidic precursors are the most abundant and play a key role in the development of wine aroma [2].

The results of experimental studies of the method based on the usage of ethyl alcohol as an internal standard for the direct determination of volatile compounds in wines and others alcohol contained products are presented. The method was validated in terms of precision, accuracy, limits of detection and quantification (lod and loq), linearity, and robustness.

Galloylated flavan-3-ols are a class of polyphenolic compounds present in various plants, including grape seeds. These compounds are formed through the condensation of flavan-3-ols, such as catechins, although the precise mechanism by which gallic acid is incorporated into the molecule remains unclear.

The objective of the present work was to study the influence of the foliar application of seaweed (Laminaria japonica), on the bunch and on the must in the ‘Cabernet Sauvignon’ grape. The experiment was carried out in the years 2021/2022, in a 21-year-old commercial vineyard, in the municipality of “Dom Pedrito” – “Rio Grande do Sul” (RS). A completely randomized experimental design was used, with 4 treatments and 4 replications (7 plants per replication). The treatments were: T1- control treatment; T2- Exal Powder 5 g L-1; T3- Hidro Exal 15 ml L-1; T4- Exal Powder 5 g L-1+ Hidro Exal 15 ml L-1.