title: Use of adsorbent and supercritical carbon dioxide to concentrate flavor compounds from orange oil.
abstract: Orange oil is composed largely of terpene hydrocarbons but is a source of flavor and fragrance compounds (oxygenated) that are present in low concentrations. To increase the ratio of oxygenated compounds to terpene hydrocarbons, orange oil was partially fractionated by adsorption of the oxygenated compounds onto porous silica gel, with full utilization of its adsorbent capacity, and then further purified by desorption into supercritical carbon dioxide. The desorption of 24 compounds was monitored by GC and GC-MS. Adsorption alone removed three-fourths of the terpene hydrocarbons, and fractional extraction by supercritical carbon dioxide (SC-CO(2)) improved the separation further. Response surface methodology was used in the experimental design, and regression analysis was used to determine the effects of process variables. Extraction at low temperatures and flow rates improved separation by SC-CO(2). Decanal was concentrated to 20 times that of the feed oil by using SC-CO(2) at 13.1 MPa, 35 degrees C, and 2 kg/h. The systems were operating at close to equilibrium conditions because of the fine dispersal of the oils and the excellent mass transfer properties of supercritical carbon dioxide.
authors.affiliation: Food Science Australia, Private Bag 16, Werribee, Victoria 3030, Australia. zhiping.shen@foodscience.afisc.csiro.au
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Shen
authors.forename: Vijay
authors.initials: V
authors.lastname: Mishra
authors.forename: Brian
authors.initials: B
authors.lastname: Imison
authors.forename: Martin
authors.initials: M
authors.lastname: Palmer
authors.forename: Robert
authors.initials: R
authors.lastname: Fairclough
mesh_terms: D000327:Adsorption; D002245:Carbon Dioxide / Q000737:chemistry*; D002849:Chromatography, Gas; D002957:Citrus / Q000737:chemistry*; D005421:Flavoring Agents / Q000737:chemistry* / Q000302:isolation & purification; D008401:Gas Chromatography-Mass Spectrometry; D007164:Immunosorbents / Q000737:chemistry; D009812:Odorants; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification*; D010938:Plant Oils / Q000737:chemistry* / Q000302:isolation & purification; D058428:Silica Gel; D012822:Silicon Dioxide / Q000737:chemistry; D013649:Taste
chemical_list: D005421:Flavoring Agents; D007164:Immunosorbents; D010936:Plant Extracts; D010938:Plant Oils; D002245:Carbon Dioxide; D058428:Silica Gel; D012822:Silicon Dioxide; C087245:orange oil