Sugar of MILK. Different methods have been proposed for obtaining the sugar of milk. The following is an account of a method used by some of the Tartar nations of preserving their milk by means of frost: in which operation great quantities of the sugar of milk are accidentally formed. The account was given by Mr. Fahrig of Peterburgh, who undertook a journey, by order of the academy of Peterburgh, among the Mogul tribes who inhabit the country beyond the lake Baikal, on the banks of the river Salenga. These people allow their milk to freeze in large quantity in iron kettles; and, when it is perfectly congealed, they place them over a gentle fire to soften the edges of the cake, after which it may be taken out with a wooden spatula. They commence these operations at the beginning of the cold, when they have milk in the greatest abundance; after which it may be preserved with great ease throughout the whole winter. Mr. Fahrig having frequent opportunities of seeing these cakes, soon observed, that the surface of them was covered to a considerable depth with a farinaceous powder; and having established a dairy upon the same plan with those of the Moguls, he found the same thing take place with himself. This powder was extremely sweet, and he received platefuls of it from the natives, who used it in their food, and sweetened their other victuals with it. Having caused a number of cakes of frozen milk to be conveyed to the top of his house, where they were directly exposed to the violent cold, he found that the separation of the saccharine powder was greatly promoted by this means. He scraped the cakes every week to the depth of two inches, and afterwards spread out the powder upon an earthen plate in order to destroy the remains of moisture which might have prevented it from keeping for any length of time. When exposed in this manner it had a very agreeable and strong saccharine taste; dissolved in warm water; and when strongly stirred by means of a chocolate stick, would at all times produce an excellent and well tasted milk. Raw milk affords a much larger quantity of this saccharine matter than such as has been boiled, or which has had the cream taken off it. Neither must the milk be suddenly exposed to the cold before it has lost its natural heat; for the sudden contact of the cold drives all the cheesy and fat part towards the middle, while the external parts consist of little else than water. In order to allow the parts of the milk to be all properly mixed together, Mr. Fahrig allowed the milk when newly taken from the cows to cool, and then poured it out into shallow kettles.
Our author is of opinion that this method of making milk would be of great service to navigators to supply themselves with milk during long sea voyages: and
Milk. he assures us, from his own experience, that it will always succeed, if proper attention be paid to it. He is of opinion, however, that all countries are not equally proper for the preparation of this saccharine matter: and indeed this seems very evidently to be the case, as the process appears to be a crystallization of the saccharine parts of the milk, and a separation of them from the aqueous ones by means of extreme cold. The country in which he made the experiments is one of the most elevated in all Asia; and so cold, that, though it lies only in the 50th degree of north latitude, its rivers are frozen up for six months of the year. A very dry cold wind also prevails throughout almost the whole year; and the dry winds generally come from the north, being almost always preceded by a warm wind from the south, which blows for some time. The dry rarefied air increases the evaporation from the ice cakes, and leaves nothing but the saccharine or pure constituent parts of the milk, which with the addition of water can always reconstitute the fluid.
Milk, in the wine trade. The coopers know very well the use of skimmed milk, which makes an innocent and efficacious forcing for the fining down of all white wines, arracks, and small spirits; but it is by no means to be used for red wines, because it discharges their colour. Thus, if a few quarts of well skimmed milk be put into a hoghead of red wine, it will soon precipitate the greater part of the colour, and leave the whole nearly white: and this is of known use in the turning of red wines, when pricked, into white; in which a small degree of acidity is not so much perceived.
Milk is, from this quality of discharging colour from wines, of use also to the wine coopers, for the whitening of wines that have acquired a brown colour from the cask, or from having been hastily boiled before fermenting; for the addition of a little skimmed milk, in these cases, precipitates the brown colour, and leaves the wines almost limpid, or of what they call a water-whiteness, which is much coveted abroad in wines as well as in brandies.
Milk of Lime; Milk of Sulphur. The name of milk is given to substances very different from milk properly so called, and which resemble milk only in colour. Such is water in which quicklime has been slaked, which acquires a whiteness from the small particles of the lime being suspended in it, and has hence been called the milk of lime. Such also is the solution of liver of sulphur, when an acid is mixed with it, by which white particles of sulphur are made to float in the liquor.
Milk of Vegetables. For the same reason that milk of animals may be considered as a true animal emulsion, the emulsive liquors of vegetables may be called vegetable milks. Accordingly emulsions made with almonds are commonly called milk of almonds. But besides this vegetable milk, which is in some measure artificial, many plants and trees contain naturally a large quantity of emulsive or milky juices. Such are lettuce, spurge, fig tree, and the tree which furnishes the elastic American resin. The milky juices obtained from all these vegetables derive their whiteness from an oily matter, mixed and undissolved in a watery or mucilaginous liquor. Most resinous gums were originally
such milky juices, which afterwards become solid by the evaporation of their more fluid and volatile parts.
Milk-Powder. See MEDICINE INDEX.