3.3. Survey of Natural Raw Materials
The following survey of the most important, well-known raw materials used in the flavor and fragrance industry is by no means complete; the materials are listed in alphabetical order. Physical standards for essential oils are described as specified by the ISO or the Essential Oil Association of the United States (EOA). Gas chromatograms are widely used for analysis and quality control, but have not been included due to lack of space. Further details are given in the literature, e.g., , and in ISO specifications, which now include gas chromatograms.
The entire components of the individual products have not been listed for the same reason; further information is available in the literature, e.g.,,. Physical data for extracts or concentrates consisting largely of nonvolatile material are not given because the composition of these products varies widely according to the isolation and manufacturing procedure used.
The botanical names of plants are cited in accordance with the International Code of Botanical Nomenclature (ICBN) as described, for example, in .
Camphor oil is obtained by steam distillation of the wood of the camphor tree Cinnamomum camphora Sieb. (Lauraceae) growing in China, Taiwan, and Japan. The main constituent of the crude oil is camphor (ca. 50%), which can be separated by cooling and centrifugation. Fractionation of the mother liquor gives two oils:
1) White camphor oil is the first distillation fraction (ca. 20% of the crude camphor oil). It is a colorless or almost colorless liquid with a cineole-like odor.
d2525 0.855– 0.875; nD20 1.4670– 1.4720; D + 16° to + 28°; solubility: 1 vol in 1 vol of 95 % ethanol; solutions usually become cloudy on further dilution .
In addition to monoterpene hydrocarbons, this oil contains up to 35% cineole.
Camphor oils with a higher cineole content can be obtained by further fractionation or by steam distillation of the leaves of other varieties of the camphor tree. They are marketed under the trade name eucalyptus oil 70–80% by Chinese producers, but are not true eucalyptus oils (see Eucalyptus Globulus Oil, Eucalyptus oils).
2) Brown camphor oil is a fraction with a boiling point higher than that of camphor (ca. 20 %). It is a pale yellow to brown liquid with the characteristic odor of sassafras oil.
d2525 1.064– 1.075; nD20 1.5100– 1.5500; D 0° to +3°; fp 6°C; solubility: 1 vol in 2 vol of 90% ethanol .
The oil contains more than 80 % safrole and, like Brasilian sassafras oil, is therefore used as a raw material for the production of piperonal via isosafrole (see Piperonal ).
Camphor oils with a high safrole content can also be obtained by steam distillation of the wood of Cinnamomum parthenoxylon Nees.
production of natural camphor and camphor oils was formerly several thousand
of tons per year, but has declined as a result of the production of synthetic
camphor. The same is true for the distillation of linalool-containing camphor
oils (Ho oil, Ho leaf oil), which are derived from other varieties of the
Sassafras oil, Brazilian is obtained by steam distillation of the roots, trunks, and branches of Ocotea pretiosa (Nees) Mez. (Lauraceae). The oil was formerly called Ocotea cymbarum oil due to incorrect botanical naming. It is a yellow to brownish liquid with the characteristic odor of safrole.
d2020 1.079 –1.098; nD20 1.5330–1.5370; D20 – 2.2° to – 0.8°; solubility: 1 vol in 2 vol of 90% ethanol; fp + 7.5 to + 9.3°C .
The main component of the oil is safrole, which may make up more than 90% of the oil and determines its freezing point.
Production from trees that grow wild in Brazil, Paraguay, and Columbia exceeds that of North American sassafras oil, which is similar in composition. Brazil produces 400 t/a. The main use of the oil is for the production of safrole and products derived from it (e.g., isosafrole and piperonal, see Sections IsosafrolePiperonal ).
Chinese sassafras oils are fractions, rich in safrole, that are obtained from oils of different species of the camphor tree (see Camphor Oils, Camphor oil).
 : H. Maarse, E. A. Visscher, Volatile compounds in Foods, Qualitative Data, TNO-Division for nutrition and food research TNO-CIVO Food Analysis Institute, Zeist (Netherlands) 1983 –1987.
 : K. Formazek, K. H. Kubeczka, Essential Oil Analysis by Capillary Chromatography and Carbon-13 NMR Spectroscopy, J. Wiley & Sons, New York 1982.
 : a) B. Lawrence, Progress in Essential Oils, bimonthly column in Perfum. and Flavor. b) Miltitzer Berichte, collection of brief reports on essential oils, flavors, and fragrances, published annually, VEB Chemisches Werk Miltitz, Miltitz (German Democratic Republic).
 : D. Zander (F. Encke, G. Buchheim, S. Seybold ed.): Handwörterbuch der Pflanzennamen, 13th ed., Verlag E. Ulmer, Stuttgart 1984.
 : Essential Oil Association of the United States No. 98.
 : Essential Oil Association of the United States No. 69.
 : ISO/DIS