Supercritical carbon dioxide hop extraction

Abstract

The hop of Magnum cultivar was extracted using supercritical carbon dioxide (SFE-as extractant). Extraction was carried out in the two steps: the first one being carried out at 150 bar and 40?C for 2.5 h (Extract A), and the second was the extraction of the same hop sample at 300 bar and 40?C for 2.5 h (Extract B). Extraction kinetics of the system hop-SFE-CO2 was investigated. Two of four most common compounds of hop aroma (?-humulene and ?-caryophyllene) were detected in Extract A. Isomerised ?-acids and ?-acids were detected too. a-Acid content in Extract B was high (that means it is a bitter variety of hop). Mathematical modeling using empirical model characteristic time model and simple single sphere model has been performed on Magnum cultivar extraction experimental results. Characteristic time model equations, best fitted experimental results. Empirical model equation, fitted results well, while simple single sphere model equation poorly approximated the results.Ispitana je ekstrakcija hmelja sorte Magnum superkriticnim ugljendioksidom (SFE-CO2) kao ekstragensom. Ekstrakcija je izvedena u dva koraka. Prvi korak pred-stavlja ekstrakciju na 150 bar i 40?S u toku 2,5 casa (ekstrakt A), a drugi ekstrakciju istog uzorka na 300 bar i 40?S u toku 2,5 casa (ekstrakt B). Ispitana je kinetika ekstrakcije sistema hmelj - SFE-CO2. U ekstraktu A detektovana su dva (?-humulen i ?-kariofilen) od cetiri uobicajena jedinjenja koja odredjuju aromu hmelja. Pored njih, detektovane su izomerizovane ?-kiseline i ?-kiseline. U ekstraktu B, sadrzaj ?-kiselina je bio visok (sto ukazuje na gorku sortu hmelja). Eksperimentalni rezultati koji se odnose na ekstrakciju hmelja sorte Magnum primenom SFE-CO2 matematicki su modelovani koriscenjem empirijskog modela, modela karakteristicnog vremena, kao i modela jedinicne sfere. Model karakteristicnog vremena najbolje je fitovao eksperimentalne rezultate. Empirijski model je dobro fitovao, dok je model jedinicne sfere lose aproksimirao eksperimentalne rezultate.