People treading grapes for red wine in Portugal. Treading grapes releases the juice. This allows the yeast Saccharomyces ellipsoideus,which occurs naturally on the skin,to ferment the sugar in the juice to alcohol. Red wine is the product of the grape with the skin,white wine is the product of the fermented pulp only. Red wine is matured in wooden casks for three to four years; oxygen passes slowly through the wood aiding the formation of esters (flavour compounds) from the alcohol and acids in the wine | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Heseltine, John |
Taille de l’image : | 3247 px × 2368 px |
Model Release : | Le droit n'est pas encore disponible. Merci de nous contacter avant utilisation. |
Property Release : | Non requis |
Restrictions : | - |