Influence of natural deep eutectic solvents on the release of volatile compounds from heated tobacco

Inspired by the emergence of natural deep eutectic solvents (DESs), we herein used thermogravimetry and pyrolysis-gas chromatography/mass spectrometry to probe the influence of six DESs (hydrogen bond acceptor=choline chloride, betaine, or l-proline; hydrogen bond donor=glycerol, 1,4-butanediol, or propylene glycol) on the release of volatiles from tobacco at 300 °C. DES treatment induced a 3.5–4.6% increase in second-stage weight loss and promoted the release of 28 aroma constituents (furans, aldehydes, ketones, and organic acids). Treatment with choline chloride-glycerol-propylene glycol increased the relative contents of the released 5-hydroxymethylfurfural and megastigmatrienone by factors of 1.2 and 3.6, respectively, whereas treatment with l-proline-glycerol promoted the release of 2,3-dihydro-3,5-dihydroxy-6-methyl-(4H)-pyran-4-one. Therefore, DES treatment facilitated the release of volatiles from tobacco powder and was inferred to be promising for the development of novel cigarette constituents.