WHALE OIL. The oils derived from whales fall into two sharply defined classes : Sperm oil, obtained from the head cavity of the sperm whale or cachalot, Physeter catodon, and the oils obtained from the right whales (genus Balaena) and the rorquals (genera Balaenoptera and Megaptera). Sperm oil is not a true fatty oil, inasmuch as it usually contains only traces of glycerides; it consists mainly of fatty acids in combination with higher mono hydric aliphatic alcohols, and is therefore included in the cate gory of liquid waxes.
Sperm whales, when fully grown, may yield up to 145 barrels of oil each ; on the average the cows yield about 25 barrels, and the bulls from 75 to 90 barrels (each barrel containing about 2301b. of oil). Large amounts of spermaceti are present in the crude oil, especially in that from the head, which is clear and liquid immediately after removal from the animal, but soon solidifies. In the refineries the oil is allowed to stand in refrigera tors for several days at a temperature of 32° F. and pressed in hydraulic presses. The oil so obtained (about 75% of the crude) will not deposit stearine at 38° F. ("cold test"), and is known as winter sperm oil. Oils having a cold test of 32° F. have also been prepared, the yield being 67%. The press residues are twice re-pressed, first at a temperature of 5o° to 6o° F. yielding about 9% of spring sperm oil and secondly at 80° F., yielding a further 5% of oil. The press cake (about II% of the crude oil) consists of crude spermaceti. Spermaceti, which consists principally of cetyl palmitate, also occurs in smaller proportions in the oils from other Cetacea. (For uses see SPERMACETI.) Sperm Oil.—Sperm oil is a pale yellow oil with a slightly fishy smell : it may be recognized by the low specific gravity, 0.875 to o.88o, the low saponification value, 125 to 13o, and the high proportion of unsaponifiable matter (about Sperm oil is largely used for the lubrication of spindles and other light machinery. It is valued on account of its free dom from gumming tendencies, and also because the viscosity decreases less with increase of temperature than is the case with mineral oils.
The oil obtained from the blubber, that is, the layer of fat immediately beneath the skin, from all species of whales other than the two mentioned above, is a true fatty oil, consisting almost entirely of glycerides. It was formerly known as "train oil" (German "Tran"). The amount of oil obtainable from the fully-grown animal varies with the species, as is shown in the following table:— Yield in barrels of Whale 31-5 gallons Right whale, Pacific . ..... 25 to 250 Atlantic 25 „ 150 Humpback whale, Pacific ..... Io „ iio )7 Atlantic . . . . . To „ IOC) Finback whale, Pacific io „ 7o „ Atlantic . . . . . 20 „ 6o Californian grey whale . . . . . . 15 „ 6o Orca or killer whale . . . . . 1 „ 6 Beluga or white whale . . . . . . i „ 3
Treating the Blubber.—The "sulphur-bottom" whale is stated to yield 6 tons of oil, 31 tons of guano and 3 cwt. of whalebone. The first quality oil is that yielded by the right whale, the "southern oil" being of lower quality. The "finner whale oil" is a still lower grade. Some whalers still "try" the blubber on board ship, although this practice has been almost superseded by the modern procedure of rendering the blubber in central stations on shore. In these stations the blubber is stripped clean from every particle of flesh as soon as possible after the capture of the whale, and cut into strips, which are then further divided in chopping machines. The mass is then placed in large pans and boiled with open steam. The oil which first runs off varies in colour from pale yellow to almost water-white. This oil has a very slight fishy smell and is known as "whale oil No. o." "Whale oil No. 1," the oil obtained on further boiling the comminuted mass, is slightly darker in colour and possesses a more pronounced odour. These two oils are stored in large vessels in tlie cold, and the deposited stearine or "whale tallow" (consist ing largely of palmitin) is removed by pressing in a hydraulic press. After removal of oil No. 1, the mass is subjected to steam in digesters at a pressure of from 4o to 5olb. per sq.in., whereby "whale oil No. 2" is obtained, which is brown in colour with a strong odour. A still darker oil, "whale oil No. 3," is obtained by adding the flesh, cut into rough lumps, together with the bones, and again digesting under steam pressure. Finally, "whale oil No 4" ("carcase oil") is obtained after the mass has putrefied; in some cases the bones are worked up separately, yielding "Whale Bone Oil." The better qualities of oil contain only small amounts of free fatty acids, and can be bleached by treatment with fuller's earth. The lower qualities of oil, however, may contain upwards of 50% of free fatty acids, and cannot always be bleached successfully. In common with other marine oils, whale oil con tains considerable amounts of highly unsaturated fatty acids, including members of the clupanodonic acid group, in which the molecule contains four pairs of doubly-linked carbon atoms.
It has yet to be seen whether blubber oils contain, as do cod liver and some fish body oils, any notable proportion of the fat-soluble vitamins.
The best quality whale oils are used as burning oils and for soap-making. When the margin of price between liquid and solid fats permits, large quantities of pale whale oil are hydrogenated (hardened), producing a white tallow-like fat suitable for edible purposes. Whale oil is also used for hatching jute and other vege table fibres, for quenching steel plates and for leather-dressing. It figures as an ingredient of lubricants for screw-cutting ma chines. The magnitude of the whaling industry may be gauged from the following figures: for the years 1925 and 1926 the pro duction of whale oil was 1,072,000 and 1,120,000 barrels respec tively. The United Kingdom imported nearly 51,000 tons in 1926. (See also OILS, FATS, AND WAXES.) (E. L.; G. H. W.)