696 MARINE PRODUCTS OF COMMERCE 



be filled at one time, closed and cooked, then opened and refilled. The rotary 

 drum, however, hastens disintegration of the bone and rendering of the oil so 

 that the time of cooking can be reduced to about 4 hours; furthermore, a good 

 grade of oil is produced. The entire residue passes off continuously as a fluid brei, 

 and is separated at a gravity separator. Formerly the nonoil residue was discarded, 

 but it is now separated from the stickwater, dried, and powdered for high-grade 

 bone meal, as is also done with the whole cooked bone at a shore station. 



The handling of viscera is subject to more opinions and techniques than other 

 parts of the whale, and the law does not require its utilization. Glands, however, 

 are sometimes removed and saved. The lungs are often discarded with the tongue, 

 as are the intestines; but sometimes some or all of them are saved. Great layers 

 of visceral fat along the mesenteries and around the heart, stomach, and kidneys 

 are almost invariably saved. Probably the best way to handle the guts is to re- 

 move the glands and layers of fat, then push or haul the whole lot into an open 

 gut tank where it can be steam-cooked with large amounts of caustic soda. The 

 oil is dark red, but may contain much vitamin A. The caustic soda neutralizes 

 much of the free fatty acid as well as breaking up the tissue. The tongue can 

 often be handled with the bones and yield a recoverable amount of oil; however, 

 it is exceedingly rubbery and hard to cut or hog. 



Products 



Products from the whaling industry may conveniently be separated into raw 

 or primary products, and derived, processed, or secondary products. Further by- 

 products of these are really part of the chemical industry. 



Primary products are fresh or salted meat for human or animal consumption, 

 baleen, ivory, ambergris, hides, and frozen glands for pharmaceuticals. 



Secondary products are oils of all kinds, meat meal, bone meal, meat extract, 

 liver oil, canned meat, etc. 



Oil. The oil from a whale depends partly on the species and partly on the con- 

 dition of the individual. Sperm and bottlenose yield waxy oil, the others glyceridic 

 oil. Sperm, humpback, and blue whales, among the larger species, are the best 

 producers. All individuals, particularly the late pregnant females, are fattest in 

 late summer after 3 or more months on the feeding grounds. 



A lean whale is distinguished by the thin body blubber with a watery inside 

 layer, no leaf fat on the body just under the blubber, and the poor quantity of 

 visceral fat. A fat whale shows thick body blubber, a firm and oily inner layer of 

 body blubber, some leaf fat between the blubber and meat, and immense deposits 

 of fat around the heart, kidneys, mesenteries, and at the base of the flipper 

 (Tveraaen, 1935, and Klem, 1935). Blubber thickness is usually measured for 

 standard on the side between dorsal fin and vent; but Slijper (1949) has proved 

 that the thickness of the blubber at the side base of the dorsal fin better indicates 

 the general condition. 



Whale oils are graded on the basis of color and free fatty acid content. Generally 

 the purchase order stipulates the maximum amount of both, and this is usually 

 under 2 per cent free fatty acid and under 5 on the yellow scale of the Lovibond 

 tintometer. Poorer grades are also sold as such, and formerly there were about 

 4 or 5 grades. Today most of the oil is No. 1, and as much poorer oil as possible 



