title: Solid-phase microextraction for determining twelve orange flavour compounds in a model beverage emulsion.
abstract: Solid-phase microextraction (SPME) coupled to gas chromatography has been applied for the headspace analysis (HS) of 12 target flavour compounds in a model orange beverage emulsion. The main volatile flavour compounds studied were: acetaldehyde, ethyl acetate, alpha-pinene, ethyl butyrate, beta-pinene, myrcene, limonene, gamma-terpinene, octanal, decanal, linalool and citral (neral plus geranial). After screening the fibre type, the effect of other HS-SPME variables such as adsorption temperature (25-55 degrees C), extraction time (10-40 min), sample concentration (1-100% w/w), sample amount (5-10 g) and salt amount (0-30% w/w) were determined using a two-level fractional factorial design (2(5-2)) that was expanded further to a central composite design. It was found that an extraction process using a carboxen-polydimethylsiloxane fibre coating at 15 masculineC for 50 min with 5 g of diluted emulsion 1% (w/w) and 30% (w/w) of sodium chloride under stirring mode resulted in the highest HS extraction efficiency. For all volatile flavour compounds, the linearity values were accurate in the concentration ranges studied (r(2) > 0.97). Average recoveries that ranged from 90.3 to 124.8% showed a good accuracy for the optimised method. The relative standard deviation for six replicates of all volatile flavour compounds was found to be less than 15%. For all volatile flavour compounds, the limit of detection ranged from 0.20 to 1.69 mg/L.
authors.affiliation: Department of Food Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Hamed
authors.initials: H
authors.lastname: Mirhosseini
authors.forename: Chin Ping
authors.initials: CP
authors.lastname: Tan
authors.forename: Salmah
authors.initials: S
authors.lastname: Yusof
authors.forename: Nazimah Sheikh Abdul
authors.initials: NS
authors.lastname: Hamid
mesh_terms: D001628:Beverages / Q000032:analysis*; D002138:Calibration; D032084:Citrus sinensis; D004655:Emulsions; D005421:Flavoring Agents / Q000032:analysis / Q000302:isolation & purification*; D008401:Gas Chromatography-Mass Spectrometry; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014835:Volatilization
chemical_list: D004655:Emulsions; D005421:Flavoring Agents