Wine fermentation process is considered successful when the quantity of yeasts – both the indigenous and the specific ones for winemaking, directly inoculated into the must – quickly overtakes the quantity of other microorganisms. This allows wine fermentation to begin and proceed smoothly, until all sugars in the must have been consumed.
The chemistry of wine fermentation is closely tied to yeasts’ metabolism of vital elements such as sugars, nitrogen-rich nutrients, vitamins, mineral salts, fatty acids and sterols.
It’s a very delicate balance – any deficiency can lead to slow or stuck wine fermentation.
Stuck fermentation can be a big problem for wine producers: this is why Perdomini-IOC has developed a broad range of wine fermentation starters which can guarantee successful alcoholic fermentation in any working conditions.
The range includes inactivated yeasts, additives to remove pesticides and to detoxify the must, special nutrients to encourage aroma metabolism and various organic, inorganic and mixed nitrogen-rich ingredients to avoid stuck fermentation in wine making.
But if stuck fermentation still doesn’t restart, the Perdomini-IOC team of expert oenologists is able to advise wineries and draw customized fermentation protocols for their individual needs.
YEAST PROTECTION
Fermentation regulators and yeast protectors
PESTICIDE REDUCTION
Fermentation starters that reduce pesticide residues
DETOXIFICATION
Fermentation starters that combat the toxicity of the ethanol
OPTIMIZATION OF THE YEAST’S AROMA METABOLISM
Special nutrients encouraging the release of aromas by the yeast
ORGANIC NUTRITION
Oenological starters for organic-nitrogen nutrition
MIXED NUTRITION
Mixed, organic and ammoniacal-nitrogen-based nutrients
INORGANIC NUTRITION
Inorganic nutrients with ammonium phosphate
Stuck fermentation in wine making: what causes it and how to solve it
In the wine producrtion, when fermentation is slow or the must doesn’t start fermenting at all, it may be best to use wine fermentation ingredients to prevent and avoid stuck fermentation.
There can be many causes of stuck or slow fermentation:
- Temperature influences the speed. Wine fermentation goes slowly and smoothly at low temperatures, on the contrary it leads to a quick start but a subsequent slow-down.
- Oxygencan produce sterols and fatty acids in the wine yeast, which are vital for transforming sugar into alcohol and protecting cells from ethanol toxicity.
- Nitrogen is a key nutrient with a major impact on the outcome of the fermentation process. A deficiency in yeast-assimilable nitrogen (YAN) limits both the growth and the fermentation activities of the yeast.
- Toxicity: the increase in ethyl alcohol leads to the formation of toxic substances which, by interacting with ethanol, compromise yeasts and the whole fermentation process.
- Natural inhibitors: in a highly toxic environment, the yeast cell membrane is not able to synthesize the so-called “survival factors”, such as fatty acids and sterols.
- Pesticide residues: the amount of pesticides used on grapes can negatively impact the nutritional substances in the yeasts able to start the wine fermentation process.
Lastly, stop-and-start fermentation can not only affect the whole vinification process but also the aromatic profile of the wines: many studies show the important link between the wine yeasts’ nutrition, the aromatic release and the overall quality of finished wines.
However, by adopting specific wine fermentation protocols and using the right wine fermentation ingredients, the winemaker can overcome many difficulties: check out our winemaking solutions and general protocols to ensure a successful wine fermentation.