Damascenone formation

Skouroumounis, G.K., Massy- Westropp, R.A., Sefton, M.A., Wifliams, P.J. (1993). 6-Damascenone Formation in juices and wines In P. Schreier P. Winterhalter (Eds.), Progress in Elavour Precursor Studies, (pp. 275-278), Allured, Publishing Corp., Carol Stream, IL. 

Coffee (Arabica) /3-Damascenone, 2-furylmethanethiol, 3-sulfanyl-3-methylbutyl formate (126), homofuronol (127), furaneol, guaiacol, 4-vinylguaiacol, methional, sotolone, 2-ethyl-3,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, vanillin, 4-ethylguaiacol, homosotolone (128) 147... 

Fig. 4.6 Mechanisms of formation of a terpenes from geraniol and geranyl glucoside b p-damascenone from megastigm-5en-7yne-3,9-diol and its glucoside...

Fig. 3 General steps for the conversion of carotenoids into flavor compounds (left) and as example A-damascenone 7 formation from neoxanthin (right).

In an acid medium, several not very odoriferous oxygenated Ci3-norisoprenoids undergo chemical modifications that may result in the formation of odoriferous /i-damascenone (Skouroumounis et al., 1992 Winterhalter, 1993) (Figure 7.5). Certain non-megastigmane Ci3-norisoprenoids, in particular TDN, are also derived from megastigmanes by chemical modifications in an acid medium (Winterhalter, 1993). However, Ci3-norisoprenoids are mainly present in grapes in the form of non-volatile precursors (carotenoids and gluco-sides). 

IsOE, S., S. Katsumura, and T. Sakan The Synthesis of Damascenone and p-Damascone and the Possible Mechanism of Their Formation from Carotenoids. Helv. Chim. Acta 56, 1514 (1973). 

In tomato paste, for example (cf. Table 17.12), it was found that the changes in aroma caused by heating are primarily due to the formation of dimethylsulfide, methional, the furanones HD2F and HD3F and the increase in P-damascenone, and a substantial decrease in (Z)-3-hexenal and hexanal. 

P-D-glucopyranoside of grasshopper ketone Figure 9.27 Formation of p-damascenone from grasshopper ketone. 

Results of this study indicated that eugenol, 1,8-cineol, linalool, and 2-isopropyl-3-methoxypyrazine are characteristic aroma compounds of the essential oil and fresh leaves of O. sanctum. Meanwhile, heating or cooking of fresh herb caused formation of additional thermally derived aroma compounds, such as )S-damascenone and other thermally derived com-... 

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