A mass spectrometry based chemical sensor consisting of a headspace autosampler directly coupled to a quadrupole mass spectrometer was used in three different food and flavor applications; strawberry flavors, whiskeys and soft drinks. This instrument integrates multivariate data analysis in which the mass spectra of the samples are used as fingerprints. Inconsistencies in raw materials…
In recent years there has been a growing demand on fast screening systems for classification of samples using their volatile composition. Typically, these samples can be analyzed by either static headspace or thermal desorption analysis. Several different approaches are possible, but common to many of the systems is that a chemometrics software package is used…
Verification of authenticity is a crucial aspect of food quality control. In particular, alcoholic beverages have been targets of numerous adulteration schemes. Addition of caramel coloring, water and lesser value whiskies to aged straight bourbons will be addressed in the present study. Unadulterated and adulterated bourbons were analyzed using a mass spectrometry based chemical sensor.…
It is known that specific compounds are produced when foods spoil. For example, commonly recognized spoilage markers include dimethyl sulfi de for chicken and eggs, diacetyl for orange juice, and trimethylamine for fish and milk. As the entire headspace of the spoiled food changes it is possible to detect the spoilage degree by measuring the…
A new technique using a chemical sensor (Gerstel, SPME ChemSensor System) consisting of a GC-MS (Agilent 6890-5973N) system with a Solid Phase MicroExtraction (SPME) autosampler (Gerstel, MPS 2) was applied to the analysis of flavor compounds in different beer sorts. The flavor compounds were extracted by SPME and analyzed with the GC-MS. The obtained GC-MS…
The aim of this study was to explore the feasibility of chemical sensor technology for the classification of coffees from different origins. As opposed to the SDEGC-MS approach, chemical sensor technology or mass spectrometry-based electronic nose can be considered as a fast analytical technique. Download PDF
Verification of authenticity is a crucial aspect of food quality control, and also important to regulatory organizations. In this study, two wines of known pure varietal along with some commercial wines were examined using a mass spectrometry based chemical sensor. The fast analysis times obtained using this instrument makes this technology ideal for detection of…
Detection of adulteration, contamination or inconsistencies in food and flavor samples should be accurate and fast. Chemical sensors are ideal for these types of applications because they provide fast measurements. While analysis times are crucial, accuracy and precision of the analysis should never be compromised. It is therefore desirable to use a reliable and stable…
An accurate but time consuming technique commonly used to analyze samples for quality control applications is Gas Chromatography / Mass Spectrometry (GC/MS). Although GC/MS is a well-known technique, analysis times are usually long and its output (a total ion chromatogram) can be hard to interpret. It is therefore of high interest to provide a faster…
A procedure to analyze several semi-polar, nitrogen-containing compounds in untreated industrial waste water by means of membrane extraction is described. The selected analytes cover a broad range of volatility and can be extracted with either chlororform or diisopropyl ether. Recoveries are 40 – 110% for test solutions containing approximately 250 μg/L. Download PDF
To perform chromatographic analysis of real-world samples, analysts often must deal with either complex sample types such as essential oils and petroleum fractions, or complex matrices like biological fluids, foods, sludge, or polymers. Once the sample has been prepared for analysis, resolution of all the individual compounds present by means of a single chromatographic separation…
A multi-residue method for determination of five groups of 85 pesticides – organochlorine, carbamate, organophosphorous, pyrethroid and others – in non-fatty food, e.g. vegetables, fruits and green tea is described. The method is based on stir bar sorptive extraction (SBSE) coupled to thermal desorption (TD) and retention time locked (RTL) GC-MS in the scan mode.…
Identification of important trace components in complex samples like fragrances, natural products, petroleum fractions or polymers can be challenging. Achieving the mass on column and resolution necessary to locate and identify trace components using a single chromatographic separation can be difficult if not impossible. Parallel detection with a selective detector and MSD can help locate…
During the past decade, miniaturized and solvent-less sample preparation techniques based on sorptive extraction, e.g. solid phase micro-extraction (SPME), have proven to be simple, fast and environmentally friendly alternatives to LLE while maintaining or even improving sensitivity. In 1999, a new extraction technique known as stir bar sorptive extraction (SBSE) using stir bars coated with…
GC analysis of complex sample types containing non-volatile materials normally requires extensive sample preparation and cleanup prior to injection to eliminate the interference from non-volatile components. Accumulation of nonvolatile matrix components in the inlet and at the head of the GC column can lead to generation of active sites, analyte degradation, poor quantitation due to…
Solid Phase Extraction (SPE) using standard cartridges is widely regarded as the method of choice to extract analytes from samples with complex matrices or to extract and concentrate analytes from a wide variety of samples in general. In this paper, an automated SPE system is presented that is based on standard cartridges. It is shown…
A fast HS-SPME-CGC-MSD method for the analysis of flavor compounds of apples was developed. A complete profile was obtained after solid phase micro-extraction within 3 minutes GC run-time using a modular accelerated column heater (MACH). Detection with a state-of-the-art quadrupole MSD allowed a data acquisition rate of 20 Hz, while the mass spectral data quality…
Various techniques employing polydimethylsiloxane (PDMS) as an extraction medium prior to GC-TOFMS analysis were investigated to measure off-flavors in aged beer. The techniques included stir bar sorptive extraction (SBSE), headspace sorptive extraction (HSSE), purge-and-trap (P&T) and closed-loop-stripping (CLS). SBSE appeared to provide the most accurate quantitation and was capable of detecting the most odor-active compounds.…