Autolysis of Wine: Meaning & Brief History
Autolysis of wine refers to a chain of complex chemical reactions that take place when wine is made to remain in contact with lees, dead yeast cells etc after fermentation process.
Autolysis is an integral part of wine production as it is a crucial component in imparting the flavour and mouth feel to the wine. The actual history of autolysis dates back to Roman Period. They were not well affluent with the details of autolysis but they understood the positive impacts of autolysis.
Autolysis & Wine Ageing: How Both Are Inter-Related?
During fermentation process, sediments remaining at the bottom of the vat of wine fermentation tank are known as lees which are mainly composed of dead yeast cells, residual sugar extracts, pulpy parts of grape, crystals of tartaric acid etc. Wine ageing on lees is a traditional ageing method for natural sparkling wines, white wines and red wines.
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For sustainable wine production, use of fine lees is preferred.
During the ageing on lees, yeasts undergo autolysis. The term autolysis literally means ‘self-destruction’, which represents the self-degradation of cellular constituents by their own hydrolytic enzymes.
This autolysis occurs just before cell death, and it is an irreversible process. Yeasts also prevent wine from oxidation as the affinity of lees for oxygen is very much higher in contrast to polyphenols present in wine.
During Autolysis, yeast cell wall do not undergo any disruption but there arise a change in its structure due to which certain compounds such as mannoproteins, polysaccharides, and other low molecular weight products etc are released from Cytoplasm and cell wall.
Mannoproteins prevent further polymerization which leads to colour stabilization in wines while Polysaccharides help in reduction of astringency of wine thereby improving the overhaul structure,
quality and mouth feel of wine.
Wine Autolysis Using
Ultrasonic: A Revolutionary Change
Ultrasonic wine ageing is a novel technique being used nowadays for commercial wine production. It is a highly reliable technique to cut down the wine ageing span on lees process.
It helps in increasing the overall concentration of polysaccharides to be released in wine barely after 15 days of treatment without affecting the overall flavor and quality of wine.
Ultrasonic treatment of wine leads to better oxidation of wine thereby catalysing the lees ageing process to a short time span.
Here are some vital aspects that make Ultrasonic Autolysis a must for wine producers
• Widely used modern technology across the industry
• Cost effective process
• Reduced time span
• Improved Wine Quality
• Better shelf life of Wine
• Hassle free in contrast to Traditional approach
• A good approach in sustainable wine making