yisalsorequiredforthesublimationofthesolventusedduringpreparationoftheextract.Moreover,themethodoftenrequiresapreviousstageofconcentration,maintainingtheproductatCuntilpartofthesolventis第页evaporated.Vacuumdistillationrequiresgreatamountsofenergytogeneratethevacuum,andcanleadtolossofcompoundsoflowmolecularweight,whichcanberemovedtogetherwiththesolventevaporatedinthesystem.EvaporationmaintainstheextractunderheatingatC,untilallthesolventisremoved.Thisprocess,inadditiontothehighdemandforenergy,candegradetheflavonoidandphenoliccompoundsinpropolis,duetothetemperatureused.However,itistheprocessthatgivesgreatereaseofimplementationincompaniesduetolowcostontheequipmentrequiredcomparedwiththepreviouscases.Theuseofmembraneconcentrationprocesseshasbeengrowingduetocertainadvantages,suchas:lowtemperatures,absenceofphasetransitionandlowenergyconsumption(Mattaetal.,).Thisprocedureisbasedontheprincipleofselectivepermeationofthesol压力对膜通量影响将温度从C上升至C并保持压强为.巴,测定温度和膜渗透性之间关系是可能。