How did we reach our main solutions, designed to preserve the freshness of white, rosé, and some red wine? Read here below how the research process developed.
Malolactic fermentation: how to prevent it?
Among the many different compounds of wine, we can find the malic acid; lactic bacteria are able to transform this acid, through malolactic fermentation (MLF), into lactic acid. MLF is, therefore, a reaction of transformation of an acid group (-COOH, proceeding from the malic acid molecule) into water and carbon dioxide, operation performed by the lactobacteria oenococcus and Lactococcus lacti.
The Winemaker can choose between two different paths:
help the MLF start by using selected lactic bacteria that, compared to indigenous strains, do not produce Biogenic Amines, compounds that may bring along a negative and often harmful biological activity;
prevent MLF in order to preserve the freshness of several white and rosé wines, and some red wines as well, by inhibiting lactic bacteria.
If the Winemaker goes for the second option, he will be able to choose one of several possibilities. Historically, in fact, to prevent malolactic fermentation in wines the winemaker may:
take extreme good care about the hygiene within the cellar;
cooling of the wine after alcoholic fermentation, which, nevertheless, brings a high energy cost with it;
add SO2, which has counterproductive effects, as the current market demand is to reduce its use;
add lysozyme to the wine, in a maximum dosage of 50g/hl. Lysozyme, however, is less and less used because of its high cost and because, being a derivative from the egg white, is considered as an allergen.
The antibacterial properties of tannins have induced Ever to search for a natural, sustainable and allergen-free solution, suitable even for the production of organic and vegan wine. In 2014 we actually presented Bluetann Pro, a product developed in our laboratories: the recommended dosage is 2g/hl, to be added directly to the must or wine.
Fumaric acid: why is Natural Control Wine more effective?
The need to protect the fix acidity of wines has led European Union to approve, according to RE 2022/68, an additive that has proved to be effective in preventing malolactic fermentation, already known and appreciated in the food industry also for its acidifying capacity: fumaric acid, which the OIV recommends in a dosage of 30-60g/hl.
Ever’s R&D has developed Natural Control Wine that, thanks to the synergy with chitosan, is more effective than the fumaric acid alone.
The addition of 30g/hl of Natural Control Wine to the wine does enhance its freshness with some increase in total acidity and some decrease in pH.
But how does this happen?
Please find, here following, some application example:
Preventing malolactic fermentation in a culture medium specific for lactic bacteria.
The tests carried out in the laboratories of Italiana Biotecnologie have been made by placing the selected lactic bacteria in the best conditions with respect to their metabolism: specific culture medium, temperature, pH, free of SO2 and Alcohol.
In the many tests, repeated in triple, the effectiveness of Natural Control Wine has been confirmed already at a dosage of 30g/hl, thanks to the synergic activity of its components, as shown by the graph on the right.
Prevention of malolactic fermentation in a culture medium specific for lactic acid.
During the past summer months, the temperatures of wines stored in non temperature controlled containers have risen over 20-25 ºC, thus favoring the MLF even in wines that had previously undergone a cross-flow filtration.
A trial, which is still in progress, has confirmed that malolactic fermentation did not take place in a wine treated with 30g/hl of Natural Control Wine: our conclusive solution.
treated with 30g/hl of Natural Control Wine: our conclusive solution.
The monitoring of the trials has been done by the Winemaker with Hyperlab instrumentation and at the cellar’s laboratory. The controls were carried out in parallel also at the laboratories of Enologica Friulana; the samples were purposely stored at 25-27 ºC, in order to facilitate a possible start of the FML.
At the time of tasting, the small changes in pH (reduction), and total acidity (which was increasing), obtained with 30g/hl of Natural Control Wine, were positively evaluated by the Winemaker.
Comparative test between Natural Control Wine and fumaric acid in wines that were kept at optimal temperature for lactic bacteria
With a different test, instead, a wine treated with 30g/hl of Natural Control Wine was compared to a treatment of 30g/hl of fumaric acid.
The analysis after 8 weeks:
In the test with 30g/hl of fumaric acid added to the wine:
– the FML is almost completed
– the wine has lost over 75% of initial malic acid
– numerous colonies of lactic bacteria can be counted
On the other hand, the test with 30 g/hl of Natural Control Wine:
– all the malic acid has been preserved
– no growth of lactic bacteria on the culture plate
Natural Control Wine with malolactic fermentation in progress
In the cellar a wine was found stored in a tank, which presented spontaneous MLF in progress.
Increasing additions of Natural Control Wine (30-45-60g/hl) were made with the aim of hindering or blocking malolactic fermentation.
The wine samples stored in laboratory, at the optimal temperature for lactic bacteria, were analyzed after 10 and 25 days from the treatment. The result is that in wine treated with 30g/hl of Natural Control Wine malolactic fermentation was not completed.
Conclusions
The optimal prevention of malolactic fermentation, within a natural and allergen-free way, is obtained by adding 30g/hl of Natural Control Wine.
How to use it best?
The addition of this solution is simple, and it should be done directly to the wine as follows:
1. disperse the dosage of Natural Control
2. Wine in 20 volumes of wine
carefully homogenize the dispersion to the mass to be treated
This procedure, besides simplifying the cellar’s operations, optimizes its effectiveness, taking advantage of the capacity of wine (hydroalcoholic solution) to solubilize fumaric acid, which is scarcely soluble in H2O.
Further information and clarifications
- In resolution OIV-OENO 618-2020 the indicated dosage is 30-60g/hl
In DELEGATED REGULATION (EU) 2022/68, fumaric acid is considered as a stabilizer - Natural Control Wine can be used in wine
- Natural Control Wine is not suitable for organic wines
- To deepen the topic, we recommend reading these articles, in Spanish and Italian.
IT