Question

what sort of treatment is planned for a barrel of wine to be "aged" for sale? (allowed to incubate with chosen woods and or chemicals for a varying period of times)

Answer 1

The term "wine aging" includes group of reaction occurring after bottling of wines. It is also referred as reductive aging since aging is carried out without oxygen. During the process of maturation and aging the most obvious change is the change in the color of wine which occurs due to phenol changes .

The various methods are used for aging of wine

1. Wine aging in oak barrels

This method was used by  ancient Roman's. It is still used but it is very slow and time consuming process . Sometimes the micro organisms like Brettanomyces and Dekkera may also contaminate the wine.

That's why new methods are developed

2 .Physical method in wine aging

a) Ultrasonic waves

Cavitation are created by ultrasonic waves in wine and the growing and collapsing of Micro size bubble also occurs. These bubbles may be precipitated by ultrasonic waves which may result in pressure and temperature increase.High temperature and pressure have negative influence on wine. So , controlled application of ultrasonic waves is must in aging of wine

During the process of aging the wine attains a peak point . At that point the quality is most fine. They have soft flavor and complex bouquet. By application of controlled ultrasonic waves this peak point is attained quickly and they maintain their fineness for a longer period of time

b) By electric field

Application of electric field cause the electroporation of cell membrane so as a result diffusion of soluble materials and microbial inactivation is increased.

The application of electric field in red wines before oak barrels positively affects the aging process time. It increases the extraction efficiency of polyphenolic compound which produces high quality wines.

c) Gamma radiation

There are three type of natural radioactivity - alpha, beta and gamma radiation. Gamma rays are the most energetic form if electromagnetic radiation.

Gamma rays are applied at determined condition which accelerates the physical maturation of wine.

However more research is to be done to understand the effects

3. By chemical methods

Micro-oxygenation

It works by the addition of oxygen at a controlled rate in red wine. This stabilize the color of wine, improve astringency ( it is a wine tasting term that refers go the tactile feeling of wine in the mouth. It refers to dry or rough feeling created in mouth by the interaction of phenolics with saliva) and aromatic components of wine.

The amount of  oxygen used is of critical importance as it is well known that the adding of oxygen affects the chemical and sensory components of wine by changing the form of phenolics, sulphur compounds and other reactions. In case of too much oxygenation there is increase in astringency, color , mouthfeel and bacterial population in wine which negatively affects the quality of wine.

This method is most popular and usually used with combination of other methods.

Below flow chart gives the summary -