Mannoproteins are a distinct yeast-derived type of polysaccharide, which are mainly used in winemaking for tartrate and protein stabilization, colour stabilization and astringency reduction.
In the world of winemaking, élevage sur lies is the term used for the process where, at the end of alcoholic fermentation, the now dead yeast cells are left in contact with the wine and periodically stirred around the wine, so that the various components arising from the autolysis of the yeast are freed and spread around the wine. Several enzymatic agents are involved in this spontaneously occurring process.
Mannoproteins can be used in winemaking as an alternative to élevage sur lies.
What are winemaking mannoproteins?
The mannoproteins used in winemaking are proteoglycans, which, unlike glycoproteins (proteins bonded to certain sugar molecules), are molecules with a high sugar content that ‘protects’ a protein. The main sugar is mannose, which is where the term ‘mannoproteins’ comes from.
When it comes to the release of mannoproteins, the quantity, speed and selectivity of this process is strongly influenced by various factors: the yeast strain used, the conditions the yeast grows in, how well fermentation has gone and the chosen method of yeast deactivation.
There are two separate stages when mannoproteins can be released:
- during alcoholic fermentation: mannoproteins are released naturally from the moment when the yeast starts growing.
- after alcoholic fermentation: mannoproteins are released when the yeast hulls (dead cells) are left in the wine and stay suspended in order to facilitate the autolysis process. This aging method is known as élevage sur lies.
What are the functions and effects of mannoproteins in wine?
- Greater stability in the structure of the wine: by interacting with other proteins and the tannins in the wine, mannoproteins lend more body and volume to the wine, as well as a richer structure. They also increase the roundness and softness of the wine, and reduce the perception of astringency and bitterness;
- Perlage management: mannoproteins increase the surface tension of the wine, stopping carbon dioxide from being freed immediately and thereby keeping the bubbles in sparkling wine, regardless of whether it’s made with the Charmat or the Traditional method;
- Tartrate stabilization: mannoproteins can also act as protective colloids and govern tartrate precipitation, preventing the formation of deposits and influencing the perception of mineral notes in the mouth;
- Colour and flavour preservation: they increase the persistence of flavours, enhance the intensity of the perceived property and help preserve colour longer;
- Astringency reduction: the unique effect mannoproteins have on tannins help reduce the bitter, astringent sensations created by tannins, lending the wine a softer, more pleasant taste
What are the advantages of Perdomini-IOC mannoproteins?
Through special extraction and purification methods, we have been able to select targeted mannoprotein elements that activate instantly and are soluble in wine. This makes them fully filtration-compatible, therefore suitable for use at the pre-bottling stage. These mannoproteins form the ultiMA range developed by the IOC R&D team.
These mannoproteins are available in both solid and liquid form; the liquid products can be added directly to the wine and have an immediate effect.
The mannoproteins in the ultiMA range have also been selected on the basis of their compatibility with the membranes used at the final filtration stage (microfiltration), making them suitable for pre-bottling treatments.
The ultiMA Jump mannoprotein is a completely new product developed in order to enhance freshness in white and rosé wines at the same time as reducing dryness and astringency. This treatment is distinguished by the significant boost it gives to the longevity of the wines it’s used on and the extraordinary persistence it gives to aromas and flavours.
Each product in the ultiMA range has a specific sensory goal. To help you find the right mannoproteins for your winery, Perdomini-IOC has developed a Dropper Box full of liquid samples for each category of treatment, which you can use to ascertain the sensory impact they have by adding a few drops to a bottle or glass of wine.
BROWSE THE BROCHURE
Want to find out more? Contact the Perdomini-IOC experts or your local area agent and try out our range of mannoproteins directly at your winery!