The genus Cinnamomum

Chemistry of Cinnamon and Cassia 89
check the commercial cinnamon oils for any adulterants. He proposed that HPLC could
be gainfully used as a quality control check for the commercial cinnamon oils.
Use of infrared spectroscopy (IR) in the analysis of cinnamon oils
Infrared spectroscopy (IR) is generally considered a tool which is complimentary to
GLC, TLC and CC in quality assessment. Shankaranarayana et al. (1975) reviewed its
applicability to the analysis of flavours. IR has been used for routine analysis of essential
oils (Carrol and Price, 1964). Wijesekera and Fonseka (1974) demonstrated the use
of IR both as a method to establish the genuineness of Sri Lankan cinnamon oils, and
also to quantitatively estimate the main constituents in them in rapid fashion, once the
standardisation of the procedure had been accomplished. Compounds such as eugenol,
cinnamic aldehyde, acetyl eugenol, cinnamyl acetate and benzyl benzoate in the leaf
oil; cinnamic aldehehyde, eugenol and cinnamyl acetate in the stem bark oil; camphor,
1,8-cineol and cinnamic aldehyde in the root bark oil can be estimated rapidly by the
technique developed by these workers. The results obtained are in close agreement with
those obtained by GLC. By comparing the IR of authentic cinnamon oil with those of
commercial oil, it is possible to detect any adulteration, or to establish the deficiency
or excess of any particular compound due to reasons like faulty distillation.
A detailed study of the chemical composition of the volatiles of cinnamon is that by
Senanayake (1977). In this study cinnamon leaf, stem bark and root bark oils from
Sri Lankan sources were analysed using GLC techniques employing a glass SCOT
column (65 m 1.6 mm OD). Prior to detailed analysis the major constituent of the
leaf oil, eugenol, was removed by means of KOH and the hydrocarbon and oxygenated
fractions were separated on silica gel columns (Table 3.4, Fig. 3.1).
Similarly in the study of stem bark oil, cinnamic aldehyde was removed using
NaHSO 3 and hydrocarbon and oxygenated fractions were separated by column
chromatography. Since root bark oil does not contain appreciable quantities of either
eugenol or cinnamic aldehyde, it was subjected to GLC analysis without prior separation.
Composition of commercial cinnamon bark oil is given in Fig. 3.2, Table 3.4.
RECORDER RESPONSE
1 3
2
7 9
4 8 10 11 15
16
6
5
12 14
17 19
22 26
24
20
30
25
27
28
34 35
32
40
36
39
0 20 40
42
49
45 48
TIME–MIN
50 52
55 57
56
58
63
62
66
68
69 70
73
74
60 80
Figure 3.1 GLC chart of non-eugenol fraction of commercial cinnamon leaf oil on SCOT column.
75