Difference between revisions of "White wine"
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After harvesting the grapes are transported to the press room, preferably in an uncrushed state to prevent undesirable excessive extraction of tannins from the stems and seeds. There they are weighed and crushed. | After harvesting the grapes are transported to the press room, preferably in an uncrushed state to prevent undesirable excessive extraction of tannins from the stems and seeds. There they are weighed and crushed. | ||
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*Pressing | *Pressing | ||
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Heat is generated during fermentation of the must and in the case of large volumes the must has to be cooled. If fermentation is finished the y | Heat is generated during fermentation of the must and in the case of large volumes the must has to be cooled. If fermentation is finished the y | ||
east settles on the tank bottom. | east settles on the tank bottom. | ||
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*Molalactic Fermentation | *Molalactic Fermentation | ||
After alcoholic fermentation and a long storage time of several weeks, low acidity wines with a pH above 3.3 often experience a decrease in the acid content. | After alcoholic fermentation and a long storage time of several weeks, low acidity wines with a pH above 3.3 often experience a decrease in the acid content. | ||
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*Development | *Development |
Revision as of 11:13, 5 May 2011
ack to EFFICENCY FINDER OF FOOD INDUSTRY
Back to Information about wine & beverages production
1. GENERAL DESCRIPTION:
- 1. General Flowsheet of red wine production
Figure 1: Production of white wine.
- 2. Description of techniques, methods and equipment
For white wine the juice is separated from seeds and skins shortly after crushing and before fermentation begins. This measure limits the uptake of most grape flavorants (aroma) and yields an almost colourless wine. Because of this white wines generally are milder tasting and may come in sweet and semisweet styles.
Best known white cultivars
- Chardonnay
- Müller-Thurgau
- Muscat blanc
- Parellada
- Pinot gris/Pinot blanc
- Riesling
- Sauvignon blanc
- Traminer
- Processing of white wine
- Acceptance of grapes
After harvesting the grapes are transported to the press room, preferably in an uncrushed state to prevent undesirable excessive extraction of tannins from the stems and seeds. There they are weighed and crushed.
- Pressing
The grapes are often stemmed before crushing. The crushed grapes are then transported into the press or into storage tanks. The untreated or treated grapes can be pressed in discontinuously operating horizontal presses or in pneumatic presses where grapes are pressed by air pressure. Freshly pressed musts still contain insoluble parts of the cellular tissue, microorganisms, crystal compounds, dirt particles… So they have to be clarified by sedimentation, centrifugation or defecation.
- Alcoholic fermentation
It is the most important step in the wine processing. One of its most important byproducts is glycerol which is an important factor in forming the body of the wine. Heat is generated during fermentation of the must and in the case of large volumes the must has to be cooled. If fermentation is finished the y east settles on the tank bottom.
- Molalactic Fermentation
After alcoholic fermentation and a long storage time of several weeks, low acidity wines with a pH above 3.3 often experience a decrease in the acid content.
- Development
After fermentation the finishing and aging processes follow. They involve the treatment of the wine with the aim of supporting the natural maturation and clarification processes and to protect the wine from undesirable changes. In the young wine a number of different processes take place; it develops a peak, termed maturity stored in a tank or in bottles. If the maturity peak is exceeded, the wine becomes firne (positive quality), but if the development continues the wine will become maderized and oxidized (decreasing quality).
- Racking
By this is meant the separation of lees from the wine by decantation. But also after decantation the wine contains invisible colloidal dissolved substances and it has to be clarified by centrifugation or filtration before bottling.
- Finning
The invisible particles in the wine are normally electrically negative charged. For removing them, particles with the opposite charge are added and the particle repulsion is neutralized. Particles form larger aggregates that sink to the bottom or float to the top.
- Sulfting
Before the filtration can take place a certain concentration of sulfurous acid has to be adjusted in the wine. It is ensured by addition of Sulfur dioxide. This step has several advantages: storage characteristics are improved, it inhibt the growth or even kill certain bacteria and also prevent browning and oxidation reactions, certain substances are reduced and taste is improved.
- Stabilization
After fining of the wine to protect it against changes, a further stabilization is necessary. The wine is cooled down to a certain temperature and a certain period to inhibit a crystalline precipitation. Before bottling the wine has to be completely clarified using filters to remove remaining particles.
- Bottling
After development of the wine in the cellar, it has to be chemically, biologically and physically stable (bottle ripe). Especially white wines have to be optically clear. A bottling line itself generally consists of several technical equipment and machines for cleaning the bottles, bottling, corking, capsuling, labelling, packing and palleting.
- 3. Temperature ranges and other parameters (table)
- 4. Benchmark data
No information is available.
2. NEW TECHNOLOGIES:
- a) Changes in the process
- No information is available.
- b) Changes in the energy distribution system
- No information is available.
- c) Changes in the heat supply system
- No information is available.
3. SOLAR SYSTEMS INTEGRATION:
Critical issues concerning the possible solar integration