[ca] La crioconcentracio es una tecnica basada en la separacio de solids solubles d&#8217;una solucio mitjancant la congelacio d&#8217;aigua. En aquest estudi ens centrarem en la criococnetracio assistida per buit, per millorar l&#8217;eficiencia del proces en la fase de separacio. Aquesta tecnica s&#8217;utilitza tant per la concentracio de suc de magrana, com per a la dessalinitzacio d&#8217;aigua. Amb la utilitzacio d&#8217;aquesta tecnologia podem obtenir concentrats d&#8217;alta qualitat i proteccio de components bioactius, la qual cosa presenta un gran avantatge respecte a altres tecnologies utilitzades per concentrar aliments liquids en la industria alimentaria. D&#8217;altra banda encara que el proces de crioconcentracio presenta un baix consum d&#8217;energia, alts factors de separacio i minima corrosio; nomes s&#8217;han realitzat estudis a escala de laboratori en la industria de dessalinitzacio. L&#8217;objectiu principal d&#8217;aquest estudi va ser analitzar les condicions optimes de pressio de buit i temps de extraccio per concentrar suc de magrana i dessalinitzar aigua. La solucio de suc de magrana i la solucio de sal es va congelar unidireccionalment a -20 &#8304;C durant 48 hores. Els resultats obtinguts presenten una major recuperacio de solids en menor temps mitjancant la tecnica assistida per buit com a font impulsora per eliminar la solucio concentrada de la matriu del gel, en comparacio d&#8217;una extraccio gravitacional. En relacio amb la dessalinitzacio d&#8217;aigua, aplicant un buit de 10 KPa durant un temps de extraccio de 45 min, es va obtenir un contingut menor de solids en el gel i per tant el proces d&#8217;obtencio d&#8217;aigua dolca es va realitzar en 3 etapes pel que fa a altres condicions estudiades. Mentre que la concentracio de suc de magrana es va obtenir un percentatge a una pressio de buit de 40 kPa i un temps de extraccio de 15 min. Per altra banda es va investigar l&#8217;us de la tecnica de crioconcentracio assistida per buit per protegir els components bioactius en l&#8217;elaboracio de suc concentrat de magrana, es va obtenir resultats amb un augment de 4 vegades en el contingut de polifenols en el concentrat (67,97% de retencio). D&#8217;altra banda es va obtenir un augment de 3 vegades en el contingut total d&#8217;acid ascorbic en el concentrat (75% de retencio). En conclusio la crioconcentracio assistida per buit es una tecnologia no solament per obtenir un concentrat amb un major contingut de solids sino tambe per obtenir components bioactius en els sucs de fruites.

[en] Freeze concentration is a technical which draws on the separation of soluble solids from a solution by freezing water. In this study, we shall be focusing in particular on vacuum-assisted freeze concentration to improving the efficiency of the process in the disengagement phase. This technique was used both for the concentration of pomegranate juice and for the seawater desalination. On using this Technology we can get high quality concentrates and the protection of bioactive components, which has a great advantage over other technologies used to concentrate liquid food in the food industry. On the other hand, although the freeze concentration process features low power consumption, high factors of separation and minimal corrosion, only at laboratory scale studies have been conducted in the desalination industry. The primary objective of this study was to evaluate the optimal conditions of vacuum pressure an suction time to concentrate pomegranate juice and desalinate water. The pomegranate juice and the salt solution were frozen unidirectionally at -20 &#8304;C for 48 hours. The results present a more solid recovery in a short time using technique of vacuum-assisted as a driving source to remove the concentrated solution of the matrix of the ice in comparison witch a gravitational extraction. In connection with desalination of water, applying a vacuum of 10 kPa for 45 min suction time was obtained one lower solids in the ice and therefore the process of obtaining fresh water was carried out in 3 stages with respect to other studied conditions. While the concentration of pomegranate juice was obtained one higher percentage of solids recovered at a vacuum pressure of 40 kPa for 15 min suction time. It also looks the use of vacuum-assisted freeze concentration technique to protect the bioactive components in the preparation of concentrated pomegranate juice, Results were obtained with a 4-fold increase in the total content of polyphenols in the concentrate (67.97% retention), on the other hand a 3-fold increase in the total content of ascorbic acid in the concentrate was obtained (75% retention). In conclusion, vacuum-assisted freeze concentration technique is a technology not only to obtain a concentrate with a higher solid content but also to protect components bioactive in fruit juices.