Palm oil

melts at 117·5° F., and is said to consist of 31 parts of stearine and 69 of oleine in 100. It becomes readily rancid by exposure to air, and is whitened at the same time. The oil extracted from the plucked tops of the pin us abies , in the Black Forest in Germany, is limpid, of a golden yellow colour, and resembles in smell and taste the oil of turpentine. It answers well for the preparation of varnishes. The oil of plum-stones , is made chiefly in Wurtemberg, and is found to answer very well for lamps. Poppy-seed oil , has none of the narcotic properties of the poppy juice. It is soluble in ether in every proportion. Rape-seed oil , has a yellow colour, and a peculiar smell. At 25° F. it becomes a yellow ma , consisting of 46 parts of stearine, which fuses at 50°, and 54 of oleine, in which the smell resides. The oils of belladonna seeds , and tobacco seeds , are perfectly bland. The former is much used for lamps in Swabia and Wurtemberg. The oil-cakes of both are poisonous. Oil of wine-stones , is extracted to the amount of 10 or 11 per cent. from the seeds of the grape. Its colour is at first pale yellow, but it darkens with age. It is used as an article of diet. FAT OIL MANUFACTURE. It is the practice of almost all the proprietors in the neighbourhood of Aix, in Provence, to preserve the olives for 15 days in barns or cellars, till they have undergone a species of fermentation, in order to facilitate the extraction of their oil. If this practice were really prejudicial to the product, as some theorists have said, would not the high reputation and price of the oil of Aix have long ago suffered, and have induced them to change their system of working? In fact all depends upon the degree of fermentation excited. They must not be allowed to mould in damp places, to lie in heaps, to soften so as to stick to each other, and discharge a reddish liquor, or to become so hot as to raise a thermometer plunged into the ma up to 96° F. In such a case they would afford an acrid nauseous oil, fit only for the woollen or soap manufactories. A slight fermentative action, however, is useful, towards separating the oil from the mucilage. The olives are then crushed under the stones of an edge-mill, and next put into a screw-pre , being enclosed in bullrush-mat bags ( cabas ), laid over each other to the number of eighteen. The oil is run off from the channels of the ground-sill, into casks, or into stone cisterns called pizes , two-thirds filled with water. The pre ure applied to the cabas should be slowly graduated. What comes over first, without heat, is the virgin oil already mentioned. The cabas being now removed from the pre , their contents are shovelled out, mixed with some boiling water, again put in the bags, and pre ed anew. The hot water helps to carry off the oil, which is received in other casks or pizes . The oil ere long accumulates at the surface, and is skimmed off with large flat ladles; a proce which is called lever l’huile . When used fresh, this is a very good article, and quite fit for table use, but is apt to get rancid when kept. The subjacent water retains a good deal of oil, by the intervention of the mucilage; but by long repose in a large general cistern, called l’enfer , it parts with it, and is then drawn off from the bottom by a plug-hole. The oil which remains after the water is run off, is of an inferior quality, and can be used only for factory purposes. The marc being crushed in a mill, boiled with water, and expre ed, yields a still coarser article. All the oil must be fined by keeping in clean tuns, in an apartment, heated to the 60th degree Fahr. at least, for twenty days; after which it is run off into strong casks, which are cooled in a cellar, and then sent into the market. Oil of almonds , is manufactured by agitating the kernels in bags, so as to separate their brown skins, grinding them in a mill, then enclosing them in bags, and squeezing them strongly between a series of cast iron plates, in a hydraulic pre ; without heat at first, and then between heated plates. The first oil is the purest, and least apt to become rancid. It should be refined by filtering through porous paper. Next to olive oil, this species is the most easy to saponify. Bitter almonds being cheaper than the sweet, are used in preference for obtaining this oil, and they afford an article equally bland, wholesome, and inodorous. But a strongly scented oil may be procured, according to M. Planché, by macerating the almonds in hot water, so as to blanch them, then drying them in a stove, and afterwards subjecting them to pre ure. The volatile oil of almonds is obtained by distilling the marc or bitter almond cake, along with water. See Pre , Hydraulic , and Stearine . Linseed, rapeseed, poppy seed, and other oleiferous seeds were formerly treated for the extraction of their oil, by pounding in hard wooden mortars with pestles shod with iron, set in motion by cams driven by a shaft turned with horse or water power, then the triturated seed was put into woollen bags which were wrapped up in hair-cloths, and squeezed between upright wedges in pre -boxes by the impulsion of vertical rams driven also by a cam mechanism. In the best mills upon the old construction, the cakes obtained by this first wedge pre ure, were thrown upon the bed of an edge-mill, ground anew, and subjected to a second pre ure, aided by heat now, as in the first case. These mortars and pre -boxes constitute what are called Dutch mills. They are still in very general use both in this country and on the Continent; and are by many persons supposed to be preferable to the hydraulic pre es. IMG:4147767755307473660_illo0899.png:Roller-mill The roller-mill, for merely bruising the linseed, ., previous to grinding it under edge-stones, and to heating and crushing it in a Dutch or a hydraulic oil-mill, is represented in figs. 770. and 771. The iron shaft a , has a winch at each end, with a heavy fly-wheel upon the one of them, when the machine is to be worked by hand. Upon the opposite end is a pulley, with an endle cord which pa es round a pulley on the end of the fluted roller b , and thereby drives it. This fluted roller b , lies acro the hopper c , and by its agitation causes the seeds to descend equably through the hopper, between the crushing rollers d , e . Upon the shaft a , there is also a pinion which works into two toothed wheels on the shafts of the crushing cylinders d and e , thus communicating to these cylinders motion in opposite directions. f , g are two scraper-blades, which by means of the two weights h , h , hanging upon levers, are pre ed against the surfaces of the cylinders, and remove any seed-cake from them. The bruised seeds fall through the slit i of the case, and are received into a chest which stands upon the board k . Machines of this kind are now usually driven by power. Hydraulic pre es have been of late years introduced into many seed-oil mills in this country; but it is still a matter of dispute whether they, or the old Dutch oil-mill, with bags of seed compre ed between wedges, driven by cam-stamps, be the preferable; that is, afford the largest product of oil with the same expenditure of capital and power. For figures of hydraulic pre es, see Pre , and Stearine . This bruising of the seed is merely a preparation for its proper grinding under a pair of heavy edge-stones, of granite, from 5 to 7 feet in diameter; because unbruised seed is apt to slide away before the vertical rolling wheel, and thus escape trituration. The edge-mill, for grinding seeds, is quite analogous to the gunpowder-mill represented in fig. 531. , page 630 . Some hoop the stones with an iron rim, but others prefer, and I think justly, the rough surface of granite, and dre it from time to time with hammers, as it becomes irregular. These stones make from 30 to 36 revolutions upon their horizontal bed of masonry or iron in a minute. The centre of the bed, where it is perforated for the pa age of the strong vertical shaft which turns the stones, is enclosed by a circular box of cast iron, firmly bolted to the bed-stone, and furnished with a cover. This box serves to prevent any seeds or powder getting into the step or socket, and obstructing the movement. The circumference of the mill-bed is formed of an upright rim of oak-plank, bound with iron. There is a rectangular notch left in the edge of the bed, and corresponding part of the rim, which is usually closed with a slide-plate, and is opened only at the end of the operation, to let the pasty seed-cake be turned out by the oblique arm of the bottom scraper. The two parallel stones, which are set near each other, and travel round their circular path upon the bed, grind the seeds not merely by their weight, of three tons each, but also by a rubbing motion, or attrition; because their periphery being not conical, but cylindrical, by its rolling upon a plane surface, must at every instant turn round with friction upon their resting points. Strong cast-iron boxes are bolted upon the centres of the stones, which by means of screw clamps seize firmly the horizontal iron shafts that traverse and drive them, by pa ing into a slit-groove in the vertical turning shaft. This groove is lined with strong plates of steel, which wear rapidly by the friction, and need to be frequently renewed. The seeds which have been burst between the rolls, or in the mortars of the Dutch mills, are to be spread as equably as po ible by a shovel upon the circular path of the edge-stones, and in about half an hour the charge will be sufficiently ground into a paste. This should be put directly into the pre , when fine cold-drawn oil is wanted. But in general the paste is heated before being subjected to the pre ure. The pre ed cake is again thrown under the edge-stones, and, after being ground the second time, should be exposed to a heat of 212° Fahr., in a proper pan, called a steam-kettle, before being subjected to the second and final pre ure in the woollen bags and hair-cloths. IMG:4147767755307473660_illo0900.png:Steam-kettle and seed-stirrers Fig. 772. is a vertical section of the steam-kettle of Hallette, and fig. 773. is a view of the seed-stirrer. a , is the wall of masonry, upon which, and the iron pillars b , the pan is supported. It is enclosed in a jacket, for admitting steam into the intermediate space d , d , d , at its sides and bottom. c , is the middle of the pan in which the shaft of the stirrer is planted upright, resting by its lower end in the step e ; f , is an opening, by which the contents of the pan may be emptied; g , is an orifice into which the mouth of the hair or worsted bag is inserted, in order to receive the heated seed, when it is turned out by the rotation of the stirrer and the withdrawal of the plug f from the discharge aperture; h , is the steam induction pipe; and t , the eduction pipe, which serves also to run off the condensed water. The hydraulic oil-pre is generally double; that is, it has two vertical rams placed parallel to each other, so that while one side is under pre ure, the other side is being discharged. The bags of heated seed-paste or meal are put into cast-iron cases, which are piled over each other to the number of 6 or 8, upon the pre sill, and subjected to a force of 300 or 400 tons, by pumps worked with a steam engine. The first pump has usually 2 or 2 1 ⁄ 2 inches diameter for a ram of 10 inches, and the second pump one inch. Each side of the pre , in a well-going establishment, should work 38 pounds of seed-flour every 5 minutes. Such a pre will do 70 quarters of linseed in the days’ work of one week, with the labour of one man at 20 s. and three boys at 5 s. each; and will require a 12-horse power to work it well, along with the rolls and the edge-stones. I am indebted to my excellent friend Mr. E. Woolsey, for the following most valuable notes, taken by him at sundry mills for pre ing oil; and remarks upon the subject of seed-crushing in general. “The chief point of difference depends upon the quality of seed employed. Heavy seed will yield most oil, and seed ripened under a hot sun, and where the flax is not gathered too green, is the best. The weight of linseed varies from 48 to 52 lbs. per imperial bushel; probably a very fair average is 49 lbs., or 392 lbs. per imperial quarter. I inspected one of the seed-crusher’s books, and the average of 15 trials of a quarter each of different seeds in the season averaged 14 1 ⁄ 2 galls. of 7 1 ⁄ 2 lbs. each; say, 109 lbs. of oil per quarter. This crusher, who uses only the hydraulic pre , and one pre ing, informed me that | Archangel seed will yield from | 15 to 16 galls. (of 71⁄2 lbs. each) | | Best Ode a | 18 and even 19 galls. | | Good crushing-seed | 151⁄2 d even 19 g do. | | Low seed, such as weighs 48 lbs. per bushel | 131⁄2 d even 19 g do. | “The average of the seed he has worked, which he represents to be of an inferior quality, for the sake of its cheapne , yields 14 1 ⁄ 2 galls. per quarter. I had some American seed which weighed 52 1 ⁄ 4 lbs. per imperial bushel, ground and pre ed under my own observation, and it gave me 111 lbs. oil; that is to say, 418 lbs. of seed gave 111 lbs. oil = 26 56 ⁄ 100 per cent. A friend of mine, who is a London crusher, told me the oil varied according to the seed from 14 to 17 galls.; and when you consider the relative value of seeds, and remember that oil and cake from any kind of seed is of the same value , it will be apparent that the yield is very different; for example, | 25th July, 1836, prices of seed. | - | | E. India linseed | worth | 52 | s. | per quarter. | | Petersburg linseed | | 48 | to 52 | do. | | Ode a | | 52 | — | — | The difference of 4 s. must be paid for in the quantity of oil which at 38 s. 6 d. per cwt. (the then price) requires about 11 1 ⁄ 2 lbs. more oil expre ed to pay for the difference in the market value of the seed. Another London crusher informed me that East India linseed will produce 17 gallons, and he seemed to think that that was the extreme quantity that could be expre ed from any seed . The average of last year’s Ru ian seed would be about 14 galls.; Sicilian seed 16 galls. | Place. | Engine Power. | Hydraulic Pre es. | Stampers. | Rollers. | Edge-stones. | Kettles. | Work done,--reduced to an hour. | Number of pre ings. | | France | 10 horse power | 1 hydraulic, 200 tons. | 5 light stampers. | 1 pair rolls. | 1 pr. edge-stones. | 5 table kettles small size heated by steam. | 1 English quarter per working hour. | 2 pre ings. | | London | 20 horse power | 1 hydraulic, 800 tons. | 13 light stampers. | 1 pair rolls. | 2 pr. edge-stones. | 8 table kettles small size heated by fire. | 2 English quarters per working hour. | 2 ditto | | London | 12 horse power, but the engine is used also for other work. | none | 9 light stampers. | 2 pair rolls, used also for other purposes. | 2 pr. edge-stones, used also for other purposes. | 4 table kettles small size heated by fire. | 7⁄8 English quarter per working hour. | 2 ditto | | Hull | 18 horse engine, old construction. | none | 3 very heavy stampers. | 1 pair rolls. | 1 pr. edge-stones. | 3 double case large size steam kettles. | 11⁄4 English quarter per working hour. | 1 ditto | | Ditto | 22 horse engine | none | 6 very heavy stampers. | 2 pair rolls. | 2 pr. edge-stones. | 6 double case large size steam kettles. | Not known. | 1 ditto | “ Rape-seed. —I have not turned my attention to quantity of oil extracted from this seed; but a French crusher (M. Geremboret), on whom I think one may place considerable dependence, told me, that | 31⁄2 | lbs. of | best Cambray rape-seed yielded | 1 lb. oil. | | 33⁄4 | — | common rape-seed | 1 lb. oil. | | 41⁄4 | — | com — on poppy-seed | 1 lb. oil. | “Rape-seed weighs from 52 to 56 lbs. per imperial bushel.” The following are the heads of a reference of machinery for a seed oil-mill :— 1. Two pairs of cast-iron rollers, 19 inches long, and 10 inches in diameter, fixed in a cast-iron frame, with bra es, wheels, shafts, bolts, scrapers, hoppers, shoes, . 2. Two pairs of edge-stones, 7 feet diameter each, with two bottom stones, 6 feet diameter each, cast-iron upright shafts, sweepers, wheels, shafts, chairs, bra es, bolts, and scrapers, with driving spur-wheels, . 3. Five steam kettles, with wheels, shafts, and bra es, bolts, breeches, and steam pipes, an upright cast-iron shaft, with chairs and bra es at each end; and a large bevel wheel upon the bottom end of upright shaft, and another, smaller, upon fly-wheel shaft, for the first motions. 4. Five stamper pre es, with pre plates of cast iron, cast-iron stamper shaft with 10 arms and 10 rollers, with bo es, bra es, bolts, driving bevel-wheels. A well made oil-mill, consisting of the above specified parts, will manufacture 200 quarters of seed per week. I have been a ured by practical engineers, conversant in oil-mills, that a double hydraulic pre , with 2 ten-inch rams, will do the work of no more than two of the stamper pre es; that is to say, it will work 22 quarters in 24 hours; while three stamper pre es will work 33 quarters in the same time, and produce one half more oil. Castor oil, quantity of , | Im- ported. | Retained for consumption. | Ex- ported. | | Year. | Cwts. | Cwts. | Cwts. | | 1835. | 1,109,307 | 670,205 | 61,296 | | 1836. | 981,585 | 809,559 | 68,515 | Duty, from British po e ions, 2 s. 6 d. per cwt.; from foreign, 1 s. per lb. Cocoa-nut oil, quantity of, | Im- ported. | Retained for consumption. | Ex- ported. | | Year. | Cwts. | Cwts. | Cwts. | | 1835. | 19,838 | 14,015 | 2,238 | | 1836. | 26,058 | 26,062 | 3,158 | | 1837. | 41,218 | 28,836 | | Olive oil, quantity of, | Im- ported. | Retained for consumption. | Ex- ported. | | Year. | Cwts. | Cwts. | Cwts. | | 1835. | 606,166 | 554,196 | 283,734 | | 1836. | 2,682,016 | 1,844,622 | 150,561 | | 1837. | 1,720,397 | 1,499,122 | | Duties on olive oil, not of Naples and Sicily, 4 d. ; of Naples and Sicily, 8 d. ; and, if in ships of these countries, 10 d. per gallon. Train oil, spermaceti, and blubber, quantity of, | Im- ported. | Retained for consumption. | Ex- ported. | | Year. | Cwts. | Cwts. | Cwts. | | 1835. | 24,197 | 16,114 | 8,035 | | 1836. | 19,489 | 18,722 | 1,365 | | 1837. | 21,823 | 21,286 | | Duties on oil taken by British ships, 1 s. ; by foreign fishers, £ 26 18 s. per tun.