Aroma from carotenoid degradation

Norisoprenoids, responsible for the typical aroma of some grape varieties, could originate from direct degradation of carotenoid molecules such as 3-carotene, lutein, neoxanthin, and violaxanthin. Some degradation carotenoid products have an important sensorial impact on wine, such as P-damascenone, P-ionone, 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN), and vitispirane. These aromatic molecules have very low olfactory perception thresholds [40]. 

P-ionone resulting from the degradation of carotenoids. Other components are the monoterpenes myrcene, a-pinene, P-pinene, a-thujene, camphene, sabinene, car-3-ene (A -carene), a-and P-phellandrene, (S)-limonene, yterpinene, p-cymene and terpinolene. p-Mentha-l,3,8-triene is the main aroma constituent of parsley leaf oil. 

The aroma and red color of the spice saffron are partly due to the style-specific accumulation of carotenoid cleavage products produced by both enzymatic and thermal degradation. M. Giaccio reviewed the renewed interest in saffron as a colorant, spice, and nutraceutical. " Crocetin is a C20 apocarotenoid derived from zeaxanthin (Figure 5.3.4B). ... 

Although the three C-10 aroma components (276) to (278) are monoterpenoids from a formal point of view, they should probably be considered as degradation products of corresponding carotenoid compounds. At any rate, this assumption was made for the formation of safranal (277) (527), the main component of saffron oil (72, 727). The ketone (278) has only been detected in Burley tobacco (777, 502). P-Cyclocitral (276) and safranal (277) were also shown to be present in tea (491). 

Some Strecker aldehydes found in many foods are listed in Table 5.16 together with the corresponding aroma quality data. Data for carbonyls derived from fatty acid degradation are found in Table 3.32. Carbonyls are also obtained by degradation of carotenoids (cf. 3.8.4.4). 

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