Analysis of the volatile components of Cheddar cheese by direct thermal desorption‐GC×GC‐TOF/MS

Abstract

Analysis of the volatile components of Cheddar cheese by direct thermal desorption-GC6GC-TOF/MSVolatile compounds were isolated from Cheddar cheese using direct thermal desorption (DTD) and analysed using comprehensive 2-D GC (GC6GC) coupled with TOF MS (TOF/MS). In total 12 aldehydes, 13 acids, 13 ketones, 5 alcohols, 3 hydrocarbons and 9 miscellaneous compounds were identified at desorption temperatures of 100, 150, 200 and 2508C using mature Cheddar cheese. A temperature of 1508C was found to be optimum for the DTD of volatiles from mature Cheddar cheese. The major components were acetic acid, butanoic acid, 3-hydroxy-2-butanone and 2,3-butanediol. A DTD temperature of 1508C was used to observe the effect of maturation (mild, medium or mature) on the volatiles of Cheddar cheese. The major components of the volatiles of mild, medium and mature Cheddar cheese were almost the same. However, their percentage compositions were found to change with the stage of maturity. DTD is simple, fast and requires only a small amount of sample (approximately 10 mg) and works well with comprehensive GC6GC-TOF/MS. Comprehensive GC also separated a number of components which remained overlapped on the single column, such as octane and hexanal.

Identification of odour-active compounds of pasteurised orange juice using multidimensional gas chromatography techniques

“…MDGC and GC-O techniques are frequently used in food flavour analysis (Cajka, Hajslová, Cochran, Holadová, & Klimánková, 2007;Chin & Marriott, 2015;Chin et al, 2012a;Gogus, Ozel, & Lewis, 2006;Komura, 2006;Williams, Ryan, Olarte Guasca, Marriott, & Pang, 2005); in this context, to the best of our knowledge, this is the first study that has combined GC-O, comprehensive two-dimensional gas chromatography (GC × GC), and heartcutting MDGC (H/C MDGC) together with accurate mass spectrometry detection (accTOFMS) for analysis of orange juice aroma. Rather than profiling the whole sample, the aim of this work was to identify the compounds of major importance for the aroma of orange juice, to evaluate the occurrence of co-elution, and implement methods for improved separation of these compounds.…”

Multidimensional and Comprehensive Two-Dimensional Gas Chromatography

“…Today, GCÂGC on both conventional and reversed column sets is preferred, with ToF MS detection for reliable identification of the detected compounds. Examples include the analysis of essential oils from the hulks of pistachio nuts extracted by direct thermal desorption (DTD) [97], from coriander leaves and hops via combined GC-OLF and GCÂGC-ToF MS [98], and from tobacco leaves [99]. In these papers, and also in studies on zedoary [100,101] essential oils and volatile oils in traditional Chinese medicines [26], it is the huge numbers of compounds detected and reliably identified that attracts most attention.…”

“…above), to directly quantify volatiles from leaves [103] and to examine the effect of maturation on the composition of Cheddar cheese volatiles [98]. This suggests that the online technique can be used advantageously in controlling production processes.…”

Instrumental Analysis of Seafood Flavour

“…If it is required to resolve one compound from another to obtain a MS identification, TOF-MS with proper software is able to make identifications and quantification frequently without the need for peak resolution [15,82]. TOF-MS has been widely used in flavour analysis of foods, such as cooked beans [104], grains [105,106], wines [107,108], olive oil [109], roasted beef [110], and Cheddar cheese [111]. In the field of seafood, it has been mainly used for quality control (fish authentication by analysis of biomarkers) [112].…”