Cooley's Cyclopaedia of Practical Receipts Volume Ii Part 57

_Answer._-- (32 / 93)(_a_ - _b_).

In translating fat into cream, the rule is that a removal of 02 gramme of fat equals a removal of 10 gramme of cream. This rule is directly founded on experiment. I do not, however, claim a high degree of accuracy for the measurement of the cream.

Finally, a slight refinement may be noticed. If a specimen of sophisticated milk has been produced by both skimming and watering, it will be obvious, on consideration, that the extraneous waters employed in manufacturing 100 grammes of it is equal to the difference between 100 and the quant.i.ty of genuine milk employed to make 100 grammes of sophisticated milk, together with a quant.i.ty of water equal to that of fat removed by skimming.

Extraneous water = 100(100 / 93)_a_ + (32 / 93)(_a_ - _b_)

= 100[(100 + 32) / 93](_a_ - _b_)

Save for the purpose of finding out the presence of matters other than an excess of water in the milk (a contingency regarded as very improbable), the estimation of the casein and milk sugar is unnecessary. The determination of the ash is for the object of learning if foreign mineral matters, such as chalk or any other inorganic impurity, are present.

Professor w.a.n.klyn says he believes that such like extraneous bodies are never employed. The chief, if not the sole, form of dishonesty are watering and skimming.

The amount of ash, however, is a good criterion as to the extent of dilution that has been practised, a deficient amount being, of course, confirmatory of a watered milk.

The determination of the amount of 'solids, not fat,' is, in almost every instance, all that is necessary to enable an opinion to be arrived at as to whether the sample of milk has had water added to it or not.

Out of fifty-six samples of milk supplied to the different London unions in 1873, Professor w.a.n.klyn reports that he found only fifteen unwatered, or nearly unwatered. Of these fifteen samples nine had been skimmed, leaving only six that were at once unwatered and unskimmed. These figures, therefore, show that only about 10 per cent. of the milk supplied in the above year to the Metropolitan unions was genuine. He adds--"It is curious to compare the language of the contract under which (as it appears from Mr Rowsell's report) the dealer supplied the various unions with milk, with the quality of the article as exhibited by the a.n.a.lysis. 'New unskimmed milk unadulterated,' 'genuine as from the cow,' 'best new unskimmed milk, to produce 10 per cent. of cream,' occur in these contracts."

_Prop._ These are well known. Perfectly fresh milk is slightly alkaline, but soon becomes acid on exposure to the air, and after a time white coagula of casein (CURDS) separate from it. This change is immediately effected by the addition of rennet or an acid. That from the first, when dried and pressed, const.i.tutes cheese.

_Pur., Tests, &c._ The common frauds practised by the milk-dealers are the addition of water and the subtraction of part of the cream. Sometimes potato starch is added to the milk, to give it a creamy or rich appearance, and this addition is still more frequently made to cream, to increase its consistence and quality.

The presence of potato starch may be determined by boiling some of the milk with a little vinegar, and after separating the coagulum by a strainer, and allowing the liquid to become cold, testing it with solution or tincture of iodine. If it turns blue, starch, flour, or some other amylaceous substance, has been used to adulterate it. In most cases it will be sufficient to apply the test to the unprepared suspected milk.

It has frequently been stated that chalk, plaster of Paris, gum, gelatin, sugar, flour, mucilage of hemp-seed, the brains of animals, and other similar substances, are often added to London milk, but there is no reason to suppose there is any truth in these a.s.sertions, as some of these articles are too costly to be used, and the presence of others would so alter the flavour or appearance of the milk, or would so soon exhibit themselves by subsidence, as to lead to their detection.

_Pres._ Milk may be preserved in stout bottles, well corked, and wired down, by heating them, in this state, to the boiling-point, in a water bath, by which means the oxygen of the small quant.i.ty of enclosed air becomes absorbed. It must be afterwards stored in a cool situation. By this method, which is also extensively adopted for the preservation of green gooseberries, green peas, &c., milk will retain its properties unaltered for years. A few grains of carbonate of magnesia, or, still better, of bicarbonate of pota.s.sa or soda, may be advantageously dissolved in each bottle before corking it.

Under Bethel's patent the milk or cream is scalded, and, when cold, strongly charged with carbonic-acid gas, by means of a soda-water machine, and the corks are wired down in the usual manner. The bottles should be kept inverted, in a cool place.

An excellent method of preventing milk from turning sour, or coagulating, is to add to every pint of it about 10 or 12 gr. of carbonate or bicarbonate of soda. Milk thus prepared may be kept for eight or ten days in temperate weather. This addition is harmless, and, indeed, is advantageous to dyspeptic patients. According to D'Arcot, 1/2000th part of the bicarbonate is sufficient for the purpose. An excess of alkali used in this manner may be detected by the milk turning turmeric paper brown, even after it has been kept some hours, and by the ash obtained by evaporating a little to dryness, and then heating it to dull redness, effervescing with an acid. (See _below_.)

? Milk should not be kept in lead or zinc vessels, as it speedily dissolves a portion of these metals, and becomes poisonous.

_Concluding Remarks._ The princ.i.p.al difference between cows' milk and human milk consists in the former containing more casein and less sugar of milk than the latter. The remarkable indisposition to coagulate is another character which distinguishes human milk from cows' milk. Prof. Falkland, who has practically investigated the subject has prepared a nutritive fluid for infants from cows' milk, closely resembling that of the healthy adult woman. His process is, however, unnecessarily complicated, and, therefore, unsuited to those who would have to employ it in the nursery.

To remove this objection we have adopted the following formula:--Sugar of milk, 2 oz.; hot water, 1/4 pint; dissolve, and, when the liquor has become quite cold, add it to fresh cows' milk, 3/4 pint, and stir them together. This quant.i.ty, prepared morning and evening, will const.i.tute the proper food for an infant of from 5 to 8 months old. More may be allowed it if it 'craves' it; but there must be no 'cramming.' At first it will be advisable to remove a little of the cream from the milk before adding to it the saccharine solution; but after a few days this will be found to be unnecessary, and, indeed, injurious. One very important particular to be attended to is, the employment of pure cows' milk, obtained from a healthy gra.s.s-fed animal only. With this precaution, and the use of a good FEEDING-BOTTLE, the infant will thrive nearly as well as on the breast of any human female, excepting its mother's. (See _below_.)

a.s.sES' MILK closely resembles human milk in colour, smell, and consistence, but it contains rather less cream. (See _below_.)

EWES' MILK closely resembles cows' milk, than which, however, it is slightly richer in cream.

GOATS' MILK, for the most part, resembles cows' milk, but its consistence is much greater, and it contains much more solid matter. (See _below_.)

MARES' MILK, in consistence; is between that of cows' and human milk. Its cream is not converted into b.u.t.ter by agitation. See b.u.t.tER, CHEESE, LACTIC ACID, &c.

_Milk as a cause or carrier of disease._--Milk of a mother labouring under strong mental emotion is, as is well known, capable of seriously endangering the health of the suckling babe. Payne narrates the case of a woman suffering under a nervous affection whose milk, two hours after an attack of the disease, became viscid, like the white of an egg. Similarly, a deterioration and consequent alteration in properties is induced in the milk of the cow if she be over driven, exhausted, or hara.s.sed. The food of the animal likewise exercises an influence on the quality of its milk; thus when cows are fed on turnips, wormwood, decayed leaves, and plants of the cabbage or onion families, the flavour of these substances is imparted to their milk. The milk of animals that have fed on poisonous or deleterious plants is capable of setting up toxic symptoms in human beings partaking of it. In June, 1875, the inhabitants of a certain quarter of Rome were attacked with an epidemic, distinguished by great gastro-intestinal irritation. The cause of the outbreak was traced to the use of goats' milk, yielded by goats that had eaten of the meadow saffron, the _Colchic.u.m autumnale_. It also appears that in the Western States of America the milk of cows that have fed on the poison-oak, the _Rhus toxicodendron_, has on several occasions given rise to attacks of illness in children, marked by extreme weakness, vomiting, fall in bodily temperature, swollen and dry tongue, and constipation. Boiling seems to remove the dangerous properties of the milk.

Milk, as has been shown by Fuchs, is sometimes infested by a fungus, the _Oidium lactis_ or _Penicillium_, which is capable of giving rise to gastric irritation, and sometimes to severe febrile gastritis.[39]

[Footnote 39: Parkes.]

Although the evidence as to the power of the milk of animals affected with epizootic diseases to convey the particular affection to human beings is contradictory, there is little reason to doubt that soured milk may become a carrier of infection from the ailing or convalescent subject to the healthy one.

Typhoid and scarlet fever have been known to have originated in this manner.

The outbreak of the former malady in Marylebone in 1874 was traced to the contamination of milk by the remains of the water which had been used in rinsing the milk pans. This water had been obtained from a well into which the excrete from a typhus patient had percolated from a privy.

At Leeds a similar outbreak was caused by the absorption by the milk of the typhoid effluvium. In the case of scarlet fever the malady has been conveyed by means of the throat-discharges and cuticle falling into the milk from the persons of servants and others employed in dairies.

=Milk, Al'mond.= See EMULSION and MIXTURE.

=Milk, Arrowroot.= _Prep._ From arrowroot, 1 table-spoonful, first wetted and stirred with a little cold water, afterwards adding, gradually, of boiling water, 1/4 pint; and, lastly, of boiling milk, 1/2 pint; with sugar, spice, wine, &c., to palate. Very nutritious, and excellent in chronic diarrha. Some persons employ all milk.

=Milk, Choc'olate.= _Prep._ Dissolve chocolate (sc.r.a.ped), 1 oz., in boiling new milk, 1 pint. Nutritious; but apt to offend delicate stomachs.

=Milk, Cof'fee.= _Prep._ 1. Coffee, 1 oz.; boiling water, 1/4 pint; infuse for 10 or 15 minutes in a warm situation, and add the strained liquid to boiling milk, 3/4 pint.

2. Coffee, 1 oz.; tie it loosely in a piece of muslin, and simmer it for 15 minutes in milk, 1 pint. Both the above have been recommended for persons of spare habits, and for those disposed to affections of the lungs, more especially for the asthmatic.

=Milk, Facti"tious.= _Syn._ ARTIFICIAL MILK. Of the numerous compounds which have been proposed as subst.i.tutes for natural milks, the following are examples:--

1. (FACt.i.tIOUS a.s.sES' MILK; LAC ASININUM FACt.i.tIUM, LAC A. ARTIFICIALE, L.)--_a._ Cows' milk, 1 quart; ground rice, 1 oz.; oringo root (bruised), 1 dr,; boil, strain, and add sugar candy (or white sugar), 1 oz.

_b._ Whites of 2 eggs; lump sugar, 1 oz.; cows' milk (new), 3/4 pint; mix, then add syrup of tolu, 3/4 oz.

_c._ Water, 1 pint; hartshorn shavings, 1 oz.; boil to a jelly; then add lump sugar, 2 oz.; cool, add new milk, 1 pint; syrup of tolu, 1/2 oz. Used as subst.i.tutes for a.s.ses' milk, taken freely as a beverage. A cupful, with or without a spoonful of rum, 3 or 4 times daily, is a popular remedy in consumption and debility.

2. (F. GOATS' MILK--A. T. Thomson.) Fresh mutton suet (minced), 1 oz.; tie it in a muslin bag, and boil it in cows' milk, 1 quart; lastly, add of sugar candy, 2 gr. In scrofulous emaciation, and in the latter stages of phthisis. The proportion of suet in the above may be advantageously increased a little. The LAC c.u.m SERO of Guy's Hospital is a similar preparation.

3. (F. HUMAN MILK; LAC HUMANUM FACt.i.tIUM, L.)--_a._ See _above_.

_b._ (Rosenstein.) Almonds (blanched), 2 in number; white sugar, 1 dr.; water, 4 fl. oz.; make an emulsion, strain, and add of fresh cows' milk, 6 fl. oz. As a subst.i.tute for the breast in nursing.

=Milk, Preserved'.= _Syn._ MILK POWDER; LACTIS PULVIS, LAC PULVERATUM, L.

_Prep._ 1. Fresh skimmed milk, 1 gall.; carbonate of soda (in very fine powder), 1-1/2 dr.; mix, evaporate to 1/3rd by the heat of steam or a water bath, with constant agitation, then add of powdered white sugar, 3-1/2 lbs., and complete the evaporation at a reduced temperature; reduce the dry ma.s.s to powder, add the cream (well drained) which was taken from the milk, and after thorough admixture put the whole into well-stoppered bottles or tins, which must be at once hermetically sealed.

2. (Legrip.) Carbonate of soda, 1/2 dr.; water, 1 fl. oz.; dissolve, add of fresh milk, 1 quart; sugar, 1 lb.; reduce it by heat to the consistence of a syrup, and finish the evaporation on plates by exposure in an oven.

_Obs._ About an ounce of the powder agitated with a pint of water, forms an agreeable and nutritious drink, and a good subst.i.tute for milk at sea.

It may also be used for tea or coffee in a solid form. This process, which is very old, has been recently patented. See MILK (_above_).

The condensed or preserved milk, now in such general use, and which is met with in tins as milk which has been more or less deprived of water by evaporation in _vacuo_. It occurs in the market in two forms--in one simply as condensed milk, and in the other as condensed milk mixed with a large quant.i.ty of sugar. Milk preserved as above without sugar will keep only for two or three days; whereas with sugar it may be preserved for an almost indefinite time. Either variety mixed with the proper quant.i.ty of water becomes normal milk again, the sweetened kind being, of course, milk with the addition of a considerable amount of cane sugar. Professor w.a.n.klyn says he has examined the princ.i.p.al brands of preserved and condensed milk sent to the London market, and finds they contain their due proportion of fat. He gives the following a.n.a.lyses of the produce of the English Condensed Milk Company:

PRESERVED MILK.

In 100 parts by weight.

Water 205 Fat 104 Casein 110 Ash 20 Cane and milk sugar 561 ------ 1000