Specific gravities citrus oils, 295

Table G1.5.7 lists the physical and chemical properties (specific gravity, SG refractive index, r optical activity, a) of citrus oils defined by the Food Chemicals Codex (NRC, 1981).

Lemon oil, prepared by expressing the peel of the nearly ripe fruit of Citrus limonum, and obtained almost entirely from Sicily and Southern Italy. Specific gravity at 15° C., 0 856-0 860 optical rotation, + 58° to + 63° refractive index at 20° C., 1 4730-1 4750 aldehydes (citral), 2 5 to 4 per cent. 

Petitgrain oil, obtained by distillation of the twigs and unripe fruit of Citrus bigaradia. There are two varieties of the oil, the French and the South American, the former being the more valuable. Specific gravity at 15° C., 0 886-0 900 optical rotation, -3° to + 6° refractive index at 20° C., 1 4604-1 4650 esters, calculated as linalyl acetate, 40-55 per cent., for the best qualities usually above 50 per cent. soluble as a rule in 2-3 volumes of 70 per cent, alcohol, but occasionally requires 1-2 volumes of 80 per cent, alcohol. 

The shaddock is the fruit of Citrus decvmana, usually known in this country as the grape fruit. It is a large fruit, native to China and Japan, and introduced into the West Indies by Captain Shaddock, whence its name. The oil, which is not known to any extent in commerce, has a specific gravity of about 860 and an optical rotation of -b 90 to 4- 95. It is a typical Citrus oil, containing much limonene, but its constituents have not yet been carefully examined. 

Umneyaiid Bennett have examined a Chinese neroll oil derived flora Citrus trip ter CL. Tt had a specific gravity 0 S50 and optical rotation +... 

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