Cryogenic trapping as a versatile approach for sample handling, enrichment and multidimensional analysis in gas chromatography.

Cryogenic methods - those that employ cryogenic fluids/gases but also other approaches to generate reduced temperature - are versatile, functional and relatively easily implemented as part of a total gas chromatographic method. The general utility of a cold region is almost invariably as a trapping or focussing step, to collect analyte into a sharp zone. The success in effectively trapping analyte depends on analyte volatility and the temperature of the cold region.

Dataset of concentrations of free terpenes at different phenological stages in L. Shiraz, Cabernet Sauvignon, Riesling, Chardonnay and Pinot Gris.

Five L. cultivars Shiraz, Cabernet Sauvignon, Riesling, Chardonnay and Pinot Gris at different E-L development stages were harvested in two experimental vintages. Temperature and rainfall data of the growing period were obtained from the Australian Government Bureau of Meteorology.

Free terpene evolution during the berry maturation of five Vitis vinifera L. cultivars.

Terpenes and their derivatives, terpenoids, are important biomarkers of grape quality as they contribute to flavor and aroma of grape and wine. The evolution of terpene and terpenoids throughout grapevine phenological development cycles is not well understood. The current study investigated the volatile profiles of free terpene and terpenoid of five widely grown Vitis vinifera L.

New approaches to monitor semi-volatile organic compounds released during coffee roasting using flow-through/active sampling and comprehensive two-dimensional gas chromatography.

A novel dynamic approach is described to profile volatile organic compound (VOC) and semi-VOC (SVOC) emission during coffee roasting aimed at analysing components present in the roasting plume, and to monitor their evolution during the process. Two sorbents - coconut shell charcoal (CSC) and styrene-divinylbenzene resin (XAD-2) - were evaluated while collecting substances in four sequential time intervals (0-3, 3-6, 6-9 and 9-12 min). Extracted VOCs (<200 Da) and SVOCs were analysed by gas chromatography (GC), and comprehensive two-dimensional gas chromatography (GC × GC) with flame ionisation (FID) and time-of-flight mass spectrometry (TOFMS) detection.

Improvement of safflower oil quality for biodiesel production by integrated application of PGPR under reduced amount of NP fertilizers.

Safflower is an important industrial oil seed and bioenergy crop in semi-arid subtropical regions due to its potential to grow on marginal land and having good percentage of seed oil contents which is an important parameter for biofuel production. However, it is an ignored crop in Pakistan. In order to improve the crop productivity and reduce the use of agrochemicals for sustainable biodiesel feedstock production, an experiment was conducted for two years to improve the fatty acid composition and oil quality of Carthamus tinctorius L.

Lipase-catalysed esters synthesis of cafestol and kahweol.

Cafestol and kahweol (C&K), two coffee diterpene alcohols with structural similarity which exhibit anticarcinogenic effects, were isolated from green coffee Arabica beans, followed by their lipase-catalysed esterification and purification by preparative high-performance liquid chromatography (HPLC). The isolation and enzymatic synthesis parameters of C&K esters were studied, with the latter optimised by a Central Composite Design; both procedures were monitored by gas chromatography. Scale up and improved isolation conditions resulted in 1.

Untargeted profiling of Glycyrrhiza glabra extract with comprehensive two-dimensional liquid chromatography-mass spectrometry using multi-segmented shift gradients in the second dimension: Expanding the metabolic coverage.

Metabolic profiling of Glycyrrhiza glabra using comprehensive two-dimensional liquid chromatography (LC × LC) coupled with photodiode array (PDA) and mass spectrometry (MS) detection is described. The separation was conducted under reversed-phase conditions, using a combination of first dimension ( D) 150 mm microbore cyano column utilising 2.7 μm diameter (d ) particles, and second dimension ( D) 50 mm superficially porous octadecylsilica column with 2.

Analysis of underivatised low volatility compounds by comprehensive two-dimensional gas chromatography with a short primary column.

Comprehensive two-dimensional gas chromatography (GC×GC) approaches with cryogenic modulation were developed for the qualitative analysis of selected low volatility compounds in raw coffee bean extracts, without derivatisation. The approaches employed short first (D) and second (D) dimension columns, specifically a D 65% phenyl methyl siloxane column (11m) and a D 5% phenyl methyl siloxane column (1m), which allowed elution of high molar mass compounds (e.g.

Comprehensive two-dimensional liquid chromatography for polyphenol analysis in foodstuffs.

Polyphenols are a class of plant secondary metabolites that are recently drawing a special interest because of their broad spectrum of pharmacological effects. As they are characterized by an enormous structural variability, the identification of these molecules in food samples is a difficult task, and sometimes having only a limited number of commercially available reference materials is not of great help. One-dimensional liquid chromatography is the most widely applied analytical approach for their analysis.

Identification of aroma-active volatiles in banana Terra spirit using multidimensional gas chromatography with simultaneous mass spectrometry and olfactometry detection.

Fruit spirits have been produced and consumed throughout the world for centuries. However, the aroma composition of banana spirits is still poorly characterised. We have investigated the aroma-impact compounds of the banana Terra spirit for the first time, using multidimensional gas chromatography (MDGC and GC × GC) in a multi-hyphenated system - i.