PikiWiki Israel 13706 Wine press in Shivta

A winepress is a device used to extract juice from crushed

grapes A grape is a fruit, botanically a berry, of the deciduous woody vines of the flowering plant genus ''Vitis''. Grapes are a non- climacteric type of fruit, generally occurring in clusters. The cultivation of grapes began approximately 8,0 ...

during

winemaking Winemaking, wine-making, or vinification is the production of wine, starting with the selection of the fruit, its Ethanol fermentation, fermentation into alcohol, and the bottling of the finished liquid. The history of wine-making stretches over ...

. There are a number of different styles of presses that are used by wine makers but their overall functionality is the same. Each style of press exerts controlled pressure in order to free the juice from the fruit (most often grapes). The pressure must be controlled, especially with grapes, in order to avoid crushing the seeds and releasing a great deal of undesirable

tannins Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids. The term ''tannin'' is widely applied to any large po ...

into the

wine Wine is an alcoholic drink made from Fermentation in winemaking, fermented fruit. Yeast in winemaking, Yeast consumes the sugar in the fruit and converts it to ethanol and carbon dioxide, releasing heat in the process. Wine is most often made f ...

. Wine was being made at least as long ago as 4000 BC; in 2011, a winepress was unearthed in Armenia with red wine dated 6,000 years old.

Press types

Basket

A basket press consists of a large basket filled with the crushed grapes. Pressure is applied through a plate that is forced down onto the fruit. The mechanism to lower the plate is often either a screw or a

hydraulic Hydraulics () is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counterpart of pneumatics, which concer ...

device. The juice flows through openings in the basket. The basket style press was the first type of mechanized press to be developed, and its basic design has not changed in nearly 10000 years.

Horizontal screw

A horizontal screw press works using the same principle as the basket press. Instead of a plate being brought down to put pressure on the grapes, plates from either side of a closed cylinder are brought together to squeeze the grapes. Generally the volume of grapes handled is significantly greater than that of a basket press.

Bladder

A bladder press consists of a large cylinder, closed at each end, into which the fruit is loaded. To press the grapes, a large

bladder The bladder () is a hollow organ in humans and other vertebrates that stores urine from the kidneys. In placental mammals, urine enters the bladder via the ureters and exits via the urethra during urination. In humans, the bladder is a distens ...

expands and pushes the grapes against the sides. The juice then flows out through small openings in the cylinder. The cylinder rotates during the process to help homogenize the pressure that is placed on the grapes.

Continuous screw

A continuous screw press differs from the above presses in that it does not process a single batch of grapes at a time. Instead it uses an

Archimedes' screw The Archimedes' screw, also known as the Archimedean screw, hydrodynamic screw, water screw or Egyptian screw, is one of the earliest documented hydraulic machines. It was so-named after the Greek mathematician Archimedes who first described it ...

to continuously force grapes up against the wall of the device. Juice is extracted, and the

pomace Pomace ( ), or marc (; from French ''marc'' ), is the solid remains of grapes, olives, or other fruit after pressing (wine), pressing for juice or Vegetable oil, oil. It contains the skins, pulp, seeds, and stems of the fruit. Grape pomace has ...

continues through to the end where it is extracted. This style of press is rarely used to produce table wines, and some countries forbid its use for higher quality wines.

Flash release

Flash release Flash release (FR) is a technique used in wine pressing. The technique allows for a better extraction of phenolic compounds and wine polysaccharides. The treatment consists of heating the grapes at 95 °C (203 °F) for several minutes with vapour ...

is a technique used in winepressing. The treatment consists of heating the grapes with steam almost to boiling and then submitting them to a strong vacuum. The technique allows for a better extraction of

phenolic compounds In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (− O H) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, . Phenolic compounds are c ...

.Effect of Flash Release Treatment on Phenolic Extraction and Wine Composition. Cécile Morel-Salmi, Jean-Marc Souquet, Magali Bes and Véronique Cheynier, J. Agric. Food Chem., 2006, 54 (12), pp. 4270–4276, .

Gallery

Image:MigdalHaemek5.jpg, Ancient winepress in

Israel Israel, officially the State of Israel, is a country in West Asia. It Borders of Israel, shares borders with Lebanon to the north, Syria to the north-east, Jordan to the east, Egypt to the south-west, and the Mediterranean Sea to the west. Isr ...

with the pressing area in the center and the collection vat off to the bottom left. Image:Wine press-bladder.jpg, A bladder press Image:Must.jpg, Old style press in

Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...

for home-made wine Image:Torkelbaum.gif, Workings of a winepress (1700s in

Ravensburg Ravensburg ( or ; Swabian: ''Raveschburg'') is a city in Upper Swabia in Southern Germany, capital of the district of Ravensburg, Baden-Württemberg. Ravensburg was first mentioned in 1088. In the Middle Ages, it was an Imperial Free City and ...

, Germany) Image:Lagar de Santurnia.jpg, Remains of a medieval winepress in the

Rioja Alavesa Rioja Alavesa (), officially Cuadrilla de Laguardia-Rioja Alavesa, in Spanish, and Biasteri-Arabako Errioxako kuadrilla, in Basque, is one of seven ''comarcas'' that make up the province of Álava, Spain. It covers an area of 315.83 km² with a po ...

File:Wine press in Hurvat Itri.jpg, Ancient winepress carved into the ground at

Hurvat Itri Horvat 'Ethri (; also spelled ''Hurvat Itri, Ethri, Atari''), or Umm Suweid (Arabic for "mother of the buckthorns"), is an archaeological site situated in the Judean Lowlands in modern-day Israel. Excavations at the site have uncovered the remai ...

, Israel

References

{{Authority control Food technology Winemaking