Simultaneous distillation and extraction

The analyses of the flavour composition of yellow passion fruits were performed by four dilferent isolation techniques, namely vacuum headspace sampling (VHS), the dynamic headspace method, simultaneous distillation and extraction at atmospheric pressure, and simultaneous distillation and extraction under reduced pressure [62]. Significant differences were found not only in the chemical composition of the resultant extracts but also in their sensory properties. The most representative and typical extract was obtained by VHS. 

The MCS collected on a Cambridge smoke pad was spiked with internal standards and subjected to simultaneous distillation and extraction by placing it in the distillation flask with 250 mL of a 12% NaCl aqueous solution, while the extract flask contained 15 mL of CH2CI2. Total transfer of the analytes (PAH, PAA and phenols) to the organic solvent was attained after 5 h boiling. The organic extract could be subjected to silylation for the phenols and amidation with heptafluorobutyric anhydride (Section III.B.l) for the aromatic amines, before end analysis by GC-MS112. 

Simmons-Smith reagent 677, 678 Simultaneous distillation and extraction (SDE) 949... 

Blood, liver, kidney, brain Sample with added sulfamic acid and antifoaming agent, subjected to simultaneous distillation and extraction, extract concentrated. GC-TEA <1 ppb 93-97% at 2.3-4.2 ppb Pylypiw et al. 1985 Pylypiw 1987... 

Forehand, J. B., Dooly, G. L., and Moldoveanu, S. C., Analysis of polycyclic aromatic hydrocarbons, phenols and aromatic amines in particulate phase cigarette smoke using simultaneous distillation and extraction as a sole sample clean-up step, J. Chromatogr., 898, 111-124, 2000. 

Analysis of PAHs, phenols and aromatic amines in particulate-phase cigarette smoke using simultaneous distillation and extraction as a sample clean-up step 53rd 1224. 

Comparison of different extraction methods Steam distillation, simultaneous distillation and extraction and headspace co-distillation, used for the analysis of the 2930. 

Isolation of the Volatile Compounds. The total reaction mass was simultaneously distilled and extracted into diethyl ether using a Likens-Nickerson (L-N) apparatus. After distillation, 5 ml of heptadecane stock solution (0.0770 g in 200 ml diethyl ether) was added to the isolate as the internal standard. After drying over anhydrous sodium sulfate and filtering, the distillate was concentrated to about 5 ml using a Kudema-Danish apparatus fitted with a Vigreaux distillation column. It was further concentrated under a stream of nitrogen in a small sample vial to a final volume of 0.2 ml. 

Table 5.8. Isolation of odorants from cherry juice -Comparison of distillation in vacuo (I) with simultaneous distillation and extraction (II)...

The very commonly used sorbic acid has been detected with low recoveries in raw beef (52-84%) by photometry, after distillation and extraction. Better recoveries ( 100%) and less manipulation have been achieved by the fluorescence technique in determination of 4-hydroxybenzoic methyl ester in nonalcoholic beverages. Additives can be present in combinations, and chromatographic methods are often used for selective individual or joint determination. Sorbic and benzoic acids have also been determined by thin-layer chromatography in beverages. This method involves minimal sample manipulation. HPLC is often the preferred method for determining additives present in mixtures, which are usually only just volatile. Simultaneous determination of additives, such as sweeteners, preservatives, and colorings in soft drinks is usually done by HPLC with UV... 

Simultaneous Steam Distillation/Extraction An elegant apparatus was described by Nickerson and Likens ( 5) for the simultaneous steam distillation and extraction (SDE) of volatile components. This device has become one of the mainstays in the flavor field. In this apparatus, both the aqueous sample and water-immiscible solvent are simultaneously distilled. The steam which contains the aroma chemicals and the organic solvent are condensed together, and the aroma compounds are transferred from the aqueous phase to the organic phase. Typical solvents used are diethyl ether, pentane or a mixture thereof normal extraction times are one to two hours. 

Blanch, G.P., Gaja, M.M., Ruiz del Castillo, M.L., Herraiz, M., and Martinez Alvarez, R. Analysis of volatile compounds in edible oils using simultaneous distillation-solvent extraction and direct coupling of liquid chromatography with gas chromatography. European Journal on Food Research and Technology, 211,45-51.2000. 

The search of adequate extraction techniques allowing the identification and quantification of wine volatile compounds has attracted the attention of many scientists. This has resulted in the availability of a wide range of analytical tools for the extraction of these compounds from wine. These methodologies are mainly based on the solubility of the compounds in organic solvents (liquid-liquid extraction LLE, simultaneous distillation liquid extraction SDE), on their volatility (static and dynamic headspace techniques), or based on their sorptive/adsorptive capacity on polymeric phases (solid phase extraction SPE, solid phase microextraction SPME, stir bar sorptive extraction SBSE). In addition, volatile compounds can be extracted by methods based on combinations of some of these properties (headspace solid phase microextraction HS-SPME, solid phase dynamic extraction SPDE). 

Reports about static HSGC and flavour research of fats and oils are scarce. HSGC can be used to good advantage when the primary aim of an analysis is quantification of target components, for example pentane or hexanal in oxidized oils. For an in-depth investigation of lipid-related flavours more sensitive techniques have to be used (Reineccius, 1989). Dynamic HS, simultaneous distillation and solvent extraction and high-vacuum... 

The alkylborane is then oxidized by the addition of 150 ml of a 15% solution of hydrogen peroxide, while the pH of the reaction mixture is maintained at 7-8 by the simultaneous addition of 3 Asodium hydroxide, the process being carried out at ice-bath temperature. The reaction mixture is neutralized and subjected to steam distillation. The distillate is extracted with ether, and the extract is dried over anhydrous magnesium sulfate. After removal of the ether, distillation yields 18.0 g (70%) of n-octanal, bp 83-85733 mm. 

Maignial, L., Pibrot, P., Bonetti, G., Chaintrau, A., and Marion, J. P. (1992). Simultaneous distillation-extraction under static vacuum Isolation of volatile compounds at room temperature. J. Chromatogr. A 606, 87-94. 

In liquid-solid extraction (LSE) the analyte is extracted from the solid by a liquid, which is separated by filtration. Numerous extraction processes, representing various types and levels of energy, have been described steam distillation, simultaneous steam distillation-solvent extraction (SDE), passive hot solvent extraction, forced-flow leaching, (automated) Soxh-let extraction, shake-flask method, mechanically agitated reflux extraction, ultrasound-assisted extraction, y -ray-assisted extraction, microwave-assisted extraction (MAE), microwave-enhanced extraction (Soxwave ), microwave-assisted process (MAP ), gas-phase MAE, enhanced fluidity extraction, hot (subcritical) water extraction, supercritical fluid extraction (SFE), supercritical assisted liquid extraction, pressurised hot water extraction, enhanced solvent extraction (ESE ), solu-tion/precipitation, etc. The most successful systems are described in Sections 3.3.3-3.4.6. Other, less frequently... 

Applications Simultaneous steam distillation-solvent extraction has been in use for many years [163]. Steam distillation combined with continuous liquid extraction is an efficient technique for the removal and isolation of volatile compounds in various matrices (environmental,... 

Solid-phase microextraction eliminates many of the drawbacks of other sample preparation techniques, such as headspace, purge and trap, LLE, SPE, or simultaneous distillation/extraction techniques, including excessive preparation time or extravagant use of high-purity organic solvents. SPME ranks amongst other solvent-free sample preparation methods, notably SBSE (Section 3.5.3) and PT (Section 4.2.2) which essentially operate at room temperature, and DHS (Section 4.2.2),... 

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