X-PRO® Verve is the activator that can also be applied in low-sulphite winemaking, ideal for obtaining wines in which the full expression of the variety and terroir is of primary importance, without any interference at the organoleptic level, in order to produce wines that respect the original concept of the product.
In order to encourage the development of fermentation, EU regulations include the use of ammonia salts, microcrystalline cellulose, thiamine hydrochloride, yeast autolysates, yeast hulls and even inactivated yeasts, which can be used at different times during the evolution of the wine.
Yeast derivatives applied for this purpose are interesting for the improvements they can bring, both in terms of the varietal expressiveness obtained in the final wine, and in terms of fermentation kinetics and processes.
Within the three definitions, autolysates, hulls and inactive yeasts, we distinguish three categories of products with different functional characteristics of interest to the winemaker. For example, they are cited for yeast activation, detoxification of the medium, the supply of microelements to support regular metabolism, etc.
But not all commercial products on the market have the same characteristics. Note, for example, that the insoluble fraction is much higher in two competitor products based solely on yeast derivatives than in V Starter Premium®, TF and Fruit. This is a typical parameter for a yeast hull and may indirectly indicate that these are two products with a limited nutritional value.
Figure 1 - Insoluble fraction present in yeast derivatives of the trade under review
The Process X-PRO®, X-PRO® Verve and fermentation activators
In order to correctly outline the characteristics of yeast derivatives, it is necessary to have a thorough knowledge of both the starting raw material and the process to obtain them. In this regard, the R&D department of Enologica Vason, after more than 5 years of experimentation, has created the X-PRO® Process, in which physical methods are preferred, in an anaerobic environment.
This exclusive process gives an enormous advantage to the researcher, as the parameters applied to the extraction technique, within certain margins, can be modified preserving the potential of the products obtained, but slightly differentiating their characteristics; in any case, they are the most respectful towards the structure of the components contained in the fresh yeast cells.
Following the presence of thiol functions in the reduced cysteine forms, it can be seen that the X-PRO® Process applied allows a higher content than a "conventional" thermal inactivation process, both in the insoluble and in the fraction already present in solution.
Figure 2 - Influence of the process temperature on the concentrations of thiol groups in inactivated yeast
The X-PRO® Process, applied to the production of fermentation activators, is able to ensure products that are easily dispersible, integral and very rich in the valuable components contained in fresh yeast cells, which at the same time possess nutritional and storage characteristics of an ideal redox system.
The new X-PRO® Verve activator can be used right from rehydration and/or in the early stages following yeast inoculation. In this way, a special fermentative well-being is observed, induced by the right supplies of valuable amino nitrogen, trace elements, sterols and cofactors. At the same time, the unique ability of X-PRO® products to regulate the redox system allows the preservation of the primary aromas of the grapes and the natural rebalancing of the aerobic reactions on the polyphenolic matrix.
The tests in Figures 3 and 4 are clear in highlighting improved kinetics compared to even the excellent organic nutrients of the V Starter range examined.
On a sensory level, the wines obtained proved to be more expressive and clear.
The must used for these trials already had an APA of 100 mg/L, 70 mg/L ammonia and 30 mg/L amine. The nutrients were all added at 20 g/hL and 16 hours after inoculation, to ensure that fermentation had started.
Figure 3 e 4 - Fermentation paths of two yeast strains (A and B) with the addition of different nutrients 16 hours after inoculation
By balancing the interventions during fermentation on the proposed nutritional model, it contributes to a very regular course, ensuring a clean metabolism, also suitable for obtaining wines with high alcohol content.
The new X-PRO® Verve activator can also be used in low-sulphite winemaking, ideal for obtaining wines that respect the original concept of the product, with full varietal and terroir expression and without any organoleptic interference.
Gianmaria Zanella – Head of Enological Research and Development Vason
Elisa Dai Prè – Enological Research and Development Vason
Fabrizio Minute - Head of Research and Development GiottoConsulting
Enrico D’Andrea – Enologic Technical Communication Manager Vason
We would like to thank Federico Giotto, founder of GiottoConsulting, for his contribution to the conception and development of the project.