Table 1.

Examples of aroma/flavour related compounds analysed with different extraction techniques in combination with GC–MS during food processing

Volatile chemical group	Main sensory attributes	Formation pathways	Extraction technique	References
Aldehydes, alcohols and ketones	Fatty Herbal Fruity Nutty Earthy	- Fatty acid oxidation - Thermal degradation of carbohydrates - Thermal degradation of amino acids - Oxidation of carotenoids	SPME, SAFE LLE SBE Dimethylacetal derivatives	Xu et al. (2007), Gao et al. (2010), Chen et al. (2015) Zheng et al. (2013) Fan et al. (2011) Berdyshev (2011)
Organic acids and derived esters	Fruity sweet-like	Lipid metabolism	SDE	Lin et al. (2014)
N- and O- containing heterocyclic compounds
Furan-derivatives	Caramel-like Fatty Nutty	- Thermal degradation of carbohydrates - Thermal degradation of amino acids - Maillard reaction - Oxidation of polyunsaturated fatty acids - Oxidation of carotenoids - Oxidation of Vitamin C	SPME AEDA	Feng et al. (2015), Seok et al. (2015) Kaneko et al. (2013), Poehlmann and Schieberle (2013)
Pyrazines	Roasted Nutty Cocoa Sweet	- Thermal degradation of amino acids - Maillard reaction	DHS, SDE	Lin et al. 2014
			SPME	Adams et al. 2008
S-containing compounds
Alkyl sulphides and polysulphides	Cooked meat aroma Alliaceous Off-flavor	- Maillard reaction - Thermal degradtion of Vitamin B1	DHS SD, SDE, SPTE, SPME LLE	Colina-Coca et al. 2013 Lee et al. (2003), Murray (2001) Tocmo et al. (2017)
Thiophenes	Meaty aroma	- Maillard reaction - Thermal degradation of Vitamin B1 - Thermal degradation of nucleotides	DHS, SDE	Lin et al. (2014), Mahadevan and Farmer (2006)
Thiazoles and thiazolines	Roasted	Interactions between Maillard reaction products and lipid-derived aldehydes	DHS	Elmore et al. (1997), Shahidi et al. (2014)

DHS dynamic headspace, LLE liquid–liquid extraction, SAFE solvent-assisted flavour evaporation, SBSE Stir-bar sorptive extraction, SD steam distillation, SDE simultaneous distillation and extraction, SPME Solid-phase microextraction, SPTE solid-phase trapping solvent extraction