Views: 10 Author: Site Editor Publish Time: 2020-01-07 Origin: Site
What are the benefits of wine membrane filtration methods compared to traditional filtration methods?
Natural clarification is the separation of suspended particulates in wine after natural precipitation, but this means does not meet the requirements of bottling commercial wines, and it must be clarified that proteins are added to adsorb suspended particulates, To accelerate the clarification process and increase clarity. At the same time, the chemical stability of wine can be improved by heating, sterilization, freezing, or aseptic filtration of wine before bottling, and removing all bacteria or yeast filtration bacteria from wine.
Natural clarification is generally used in wine clarification, original wine brewing, thermal stability treatment, raw wine composition adjustment, thermal stability treatment and other production processes. Due to the long period of natural clarification, it is generally required to prohibit and maintain a certain amount of sulfur dioxide at low temperature, and then combine mechanical clarification and chemical clarification to achieve the purpose of clarification.
Wine is a wine whose volume fraction of low nutritional alcohol is more than 16% because of the germicidal and bacteriostatic effect of alcohol. Bottling usually does not cause biological spoilage of sugar-containing wines with a volume fraction of less than 16% because alcohol content is low if it is not bottled by aseptic filling and then sterilized, which may lead to fermentation after bottling.
Therefore, the filling of wine must be sterilized with steam in the pipeline of the wine conveying by precision filter bacteria, the empty bottle must be sterilized with sulfur dioxide, the bottle cap or cork must be strictly sterilized to make the pour wine, the wine bottle, the bottle cap and the wine delivery pipe are all sterile. So that the wine will not be fermentative.
deep clarification filtration and thin film filtration
At present, membrane filtration is widely used as terminal filter in wine industry, and it has become an essential unit operation. The most commonly used method is to combine deep clarification filtration with membrane filtration.
The wine making process modified by membrane technology is as follows: grape → crushing → pressing → grape juice → ultrafiltration clarification → fermentation → microfiltration → aging → ultrafiltration → bottling.
Ultrafiltration is mainly used to clarify grape juice before fermentation and to filter the wine that has been prepared for bottling after fermentation, while microfiltration is used for the removal of yeast.
Ultrafiltration treatment of grape juice can remove colloids, macromolecular tannins, polysaccharides, hybrid proteins, suspended solids, polyphenols and other useless microorganisms.
Ultrafiltration improves the stability of the wine. Wine turbidity is caused by unstable proteins or insoluble proteins under acidic conditions. The traditional method is to remove it with diatomaceous earth filtration, but this will lose some flavor, while ultrafiltration not only removes these proteins but also minimizes the loss of taste.
Polyphenols give the wine a color and a subtle complex taste, and excessive polyphenols can cause bitterness. Gelatin is usually added to remove excess polyphenols, and gelatin and polyphenols form a polyphenol-protein complex that needs to be removed by filtration. Ultrafiltration can reduce the polyphenol content but not all of it. However, since polyphenol oxidase is also removed by ultrafiltration, the application of ultrafiltration improves the color and taste stability of the wine.