Ammonium sulfate

Ammonium sulfate is a chemical compound that comes in the form of perfect white crystals and is easily dissolved in the must in a short time. In oenology, ammonium sulfate is used as a fermentation activator to provide assimilable nitrogen to yeast cells during the must fermentation process. The following are some of its main characteristics and advantages in its use in enology:

• Readily assimilable nitrogen supply (RAN): ammonium sulfate is a direct source of assimilable nitrogen for yeast during alcoholic fermentation. Nitrogen is an essential nutrient for yeasts and affects their ability to complete fermentation efficiently. Sufficient nitrogen can prevent unwanted fermentation arrests.
• Prevention of hydrogen sulfide formation: during fermentation, yeasts can produce hydrogen sulfide, which is known to have an unpleasant smell similar to rotten eggs. The addition of ammonium sulfate in combination with oxygen brought in through air repassing can help prevent the formation of hydrogen sulfide.
• pH management: the addition of ammonium sulfate can affect the pH of the treated solution. It is important to keep in mind that pH may vary when using this additive.
• Limitation of phosphate-ferric case risks: the use of ammonium sulfate, as opposed to the exclusive use of Diammonium Phosphate (DAP), can help limit the risks of phosphate-ferric case formation, which can cause colloidal instability problems in wines.
• Sulfate concentration: the addition of ammonium sulfate will increase the concentration of sulfates in the treated must or wine. It is important to monitor these parameters to ensure compliance with legal limits.