Myrcene parsley

The major constituents of parsley leaves are 1,3,8-p-menthatriene, followed by /)-phellandrene, myristicin and myrcene. Parsley accessions high in the specific constituents (percentage of essential oil)... 

Parsley (Petroselinum crispum) is a member of the Apiaceae family. The fresh leaves of parsley and the dried herb are widely used as flavouring. More than 80 compounds have been identified in the volatile fraction, and the aromatic volatiles of parsley are mainly monoterpenes and the aromatics myristicin and api-ole. It is suggested that the characteristic odour of parsley is due to the presence ofp-mentha-l,3,8-triene, myrcene, 3-sec-butyl-2-methoxypyrazine, myristicin, linalool, (Z)-6-decenal and (Z)-3-hexenal [227, 228]. Furthermore, /3-phellan-drene, 4-isopropenyl-l-methylbenzene and terpinolene contribute significantly... 

Fig. 16.2 Flavour dilution (FD) chromatogram obtained by application of aroma extract dilution analysis on an extract prepared from parsley leaves. The odorants were identified as 1 methyl 2-methylbutanoate, 2 myrcene, 3 l-octen-3-one, 4 (2)-l,5-octadien-3-one, 5 2-isopropyl-3-me-thoxypyrazine, 6p-mentha-l,3,8-triene, 71inalool, 8 2-sec-butyl-3-methoxypyrazine, 9 (.Z)-6-dece-nal, 10 / -citronellol, 11 ( , )-2,4-decadienal, 12 / -ionone, 13 myristicin, 14 unknown. RI retention index. [30, 31]...

The celery x parsley hybrid inherited all the terpenoids from celery and heptanol from parsley, while synthesizing new compounds of its own. The content of these new compounds was higher than that of the main celery components, limonene and myrcene (Madjarova et al., 1979). The volatile components of celery consisted of monoterpene hydrocarbons (46.0%) and phthalides (42.3%). The major components were limonene and 3-butyl-4,5-dihydrophthalide (or sedanenolide). Celery volatiles contained higher concentrations of y-lerpinene and a-pinene. A celery-like odour was associated during GC elution with each of the 16 phthalides reported (MacLeod and Ames, 1989). 

The most important odorants of parsley leaves are listed in Table 6.48. An aroma model formulated on the basis of the quantitative data (Table 6.48) was described as clearly parsley-like [88]. Differences between the odour profile of the model and that of parsley leaves were observed for the spicy and the green-grassy notes which were stronger and weaker, respectively, in the model. The parsley-like character of the aroma model was completely lost when p-mentha-l,3,8-triene (no. 1 in Table 6.48) and myrcene (no. 2) were omitted [88],... 

Myrcene is a hydrocarbon which occurs in many essential oils such as those obtained from parsley leaf, rosemary, celery leaf, hops, lemon-grass, cardamom seeds and blackcurrant buds. It is also obtained when P-pinene, a major constituent of turpentine, is heated to a high temperature. It has a pleasant odour for a hydrocarbon, being described as sweet, balsamic, herbal and refreshing. 

Production By steam distillation of the aerial parts of the parsley plant, including the unripe seeds. Composition A major part of the oil consists of monoterpene hydrocarbons such as a- andP- pinenes, myrcene, limonene, P-phellandrene (see p-mentha-dienes). The occurrence of p-mentha-1,3,8-triene (usually between 20 and 30%) (C,oH,4, Mr 134.22) is characteristic and mainly responsible for Ae organoleptic impression. According to recent investigations a series of other trace components with widely varying structures also contributes to the typical parsley odor. The leaf oil also contains lower concentrations of those compounds that constitute the main components of parsley seed oil (see below). 

The most important odorants of parsley leaves are listed in Table 22.8. Sensory evaluations have shown that p-mentha-l,3,8-triene (X in Formula 22.3) and myrcene contribute to the characteristic aroma. (Z)-6-Decenal and (Z)-3-hexenal are responsible for the green notes. Myristicin, 2-5ec-butyl-3-methoxypyrazine, (E,E)-2,4-deca dienal, methanethiol and P-phellandrene also... 

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. 

Parsley herb (leaf) oil contains myristicin (up to 85% in the curly moss variety), P-phellandrene, 1,3,8-p-menthatriene, myrcene, apiole, terpinolene, and l-methyl-4-isoprope-nylbenzene as major components. Other compounds present include a- and P-pinenes, fra 5-p-ocimene, y-terpinene, methyl disulfide, a-terpineol, a-copaene, caryophyllene, and carotol, among others.An assessment of 104 accessions found leaf oil content to range from 0.00% to 0.16% (fresh weight). Major constituents were 1,3,8-p-menthatriene (68%), myristicin (60%), P-phellandrene (33%), apiol (22%), myrcene (16%), plus terpinolene and l-methyl-4-isopropenylben-zene at 13%. Thymol, first reported for the leaf oil, was found at 2% or less in seven samples. More than 45 components have been reported from parsley leaf oil. ... 

Key parsley aroma compounds were recently identified (41). The primary flavor contributors were found to include p-mentha-l,3,8-triene (terpeny, parsleylike), myrcene (metallic, herbaceous), 2-sec-butyl-3-methoxypyrazine (musty, earthy), myristicin (spicy), linalool (coriander), (Z)-6-decenal (green, cucumber), and (Z)-3-hexenal (green). 

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