Skimmed or Separated Milk.

In referring to this product of the daily, I quote those portions of my last paper upon "The Utilisation of Skimmed Milk," and of Mr. Stephenson's paper upon the same subject—both of which were read before the Conference of British Dairy-farmers—which more distinctly apply to colonial dairying :—

There is no question more difficult to solve than how to profitably utilise skimmed or separated milk. I do not pretend to indicate any new or extraordinary method, inasmuch as in a previous year I have suggested such means of sale as had not already been adopted—although these suggestions called forth a considerable amount of hypercriticism; but I shall place a few succinct ideas before the Conference in connection with the various channels through which it is possible for skimmed milk to pass.

The casein is identical with the casein of new milk, and it is the leading principle in all the best cheeses, including the "Cheddar of the world." It is also equivalent in food-value to the most valuable constituent in the flesh of animals, and is a food absolutely necessary to life. Although butter is regarded as the most valuable constituent of milk, it is not so essential to the life, whether of man or animals, as casein or its albuminoid equivalent, for, as my friend Mr. Lloyd, the chemist to the Association, says, in one of the ablest papers I ever read—"The Value of Cattle Foods," in the "Live-stock Journal Almanack"—"Albuminoids can take the place of carbo-hydrates or fat, because they contain carbon, yet fat and carbo-hydrates, as they do not contain nitrogen, cannot take the place of albuminoids." Casein, then, I do not believe to be sufficiently valued. Albumen, another nitrogenous constituent, is equally valuable, and resembles the albumen of an egg, but it does not enter into the composition of cheese—at all events, of British cheese. The sugar of milk, like the casein, is almost entirely left in the skimmed milk. It can be obtained in crystals by evaporation, and it is composed of carbon, hydrogen, and oxygen, the two latter holding the same relative positions that they hold in pure water. Hence the term applied to it as a carbo-hydrate. Sugar is a warmth-giving food, and it or its equivalent is necessary to healthy life.

Condensed skim-milk is a food worthy of the attention of some energetic capitalist. In a remote dairying district, where skim-milk can be purchased cheaply, this article might be made to sell retail in sixpenny tins of 2lb. weight, and at this price I believe it would prove a formidable rival to the richer brands, although I do not think it would in any way endanger the trade. There are hundreds of thousands of families who value skimmed milk very highly as a food, but who cannot obtain it, and a well-made condensed milk would largely meet their requirements. This reminds me that if a tinned cream, prepared to keep a few weeks, was placed on the market it would be likely to meet with success.

For conversion into cheese, skimmed milk is not sufficiently utilised or understood. An ordinary "Skim Dick" is a thing to be remembered by the dyspeptic. There is, however, no necessity for the manufacture of an article so inferior. A study of cheesemaking—far too uncommon where skim-cheese is made—would enable any person to greatly improve it. I would especially refer to the fact that a capital cheese can be made upon the principle which I have adopted in making Gorgonzola. This system adds an agreeable flavour, whereas the absence of pressure prevents the toughness so disagreeable in skim-cheese. Of soft skim-cheeses I have spoken sufficiently often; of their profitable nature and their value a food there can be no doubt. Like other soft cheeses, they will keep for months; but the public prefer them fresh, as they dry with age, and, containing no fat, become harsh and strong in flavour.

In estimating the value of skim-milk as a food for animals it will page 38 be as well to compare it with hay, which is much better appreciated than almost any other kind of cattle-food. A fair analysis of the constituents of hay is—

	per cent.
Albuminoids	9.0
Fat	2.5
Carbo-hydrates	40.0
	51.5

I believe hay to be worth this amount per ton when it is composed of good grasses which have been well saved, whereas no one can well dispute the value of the milk, which is arrived at by the same process of reasoning, with this exception : that the whole of the solid constituents of the milk are estimated as digestible, whereas the fibre of the hay and the manurial value of both foods is omitted. Upon this basis skim-milk is worth 1.36d. per gallon. Supposing, however, that in practice the fat of new milk is substituted by oil at the rate of 70lb. to the ton, and costing 5d. per pound, we get what is practically equivalent to new milk, a ton of which, costing upon the above basis £2 14s. 2d., would fatten two strong calves. Here we get some assistance from the centrifugal separator, which will thoroughly mix the two foods for this purpose.

Lastly, skim-milk can scarcely be overestimated as a food for pigs, although it does not return so large a profit in this direction. To utilise it to the best advantage it should be mixed with meals rich in carbon, such as barley-meal and maize, and in conjunction with these foods it produces the richest pork in the world. Experiments both at Rothamsted and in America have shown that a bushel of 60lb. of maize is capable of conversion into 12lb. of pork. It is also equal to 70 gallons of skim-milk. Consequently, as maize can be purchased at £1 a quarter, skim-milk, as compared with it, is worth less than ½d. per gallon; but as, by the same rule, 6 gallons of milk is equal to the manufacture of 1lb. of pork worth 6d., I shall not be accused of extravagance in assigning it a value as a pig-food of 1d. per gallon.

Mr. Stephenson says: "A scientific American farmer, who favours me with occasional communications on dairying subjects, found by careful experiments conducted by himself that 100lb. skim-milk made 6¼lb. of pork, which at 3d. per pound would pay 1.87d. per gallon; or, if the price were 5d. per pound for pork, the skim-milk would be paid for at the rate of 3.12d. per gallon. From this will appear the fallacy of putting any fixed price on skim-milk, irrespective of current fluctuations in the value of the article its consumption is intended to produce, as has very frequently been done, to the great perplexity of those who have attempted a study of the subject."

Other careful feeders in America give it as their opinion that 100lb. of skim-milk, or about 10 gallons by measure, is equal in feeding-value to 60lb. of maize, when fed together with that grain, which, at 5s. per 100lb. for the maize, would make the value of the skim-milk to be 3d. per gallon, closely approximating the last estimate.

When fed with grains rich in starch, such as rice, maize, or potatoes. the best and most economical results will be obtained.

Its value for calf-rearing is well known, although its use for that purpose is not always applied as in the interests of economy it might be. Whilst most desirable that the calf should have the mother's milk for some days at the first, we believe that by substituting a small but gradually-increasing quantity of boiled linseed with separated milk, a much greater quantity of butter might be made with increased profit to the producer. When, for instance, butter is selling at 1s. 4d. per pound, one-twelfth of the sum obtainable for the butter expended in linseed will replace the milk-fat removed from the milk to produce the butter; or, in other words, by the addition of about 10oz. of linseed to 1 gallon of separated milk, the fat taken out for butter-making is replaced at one-twelfth the amount realised for the latter. To give the figures: linseed contains about 34 per cent, of oil, and 30 percent, of carbo-hydrates equal to about 15 per cent, of fat—say 50 per cent, in all; so that 10oz. of linseed would contain 5oz. of fat, costing 1¼d. per pound.

One ounce of rice or white bread contains about 180gr; of fat (reckoned as starch), so that to replace the 311½gr. of fat taken out of whole milk by separation, we only require to add to 1 pint of skimmed milk 1.73oz.—say 1¾oz.—of either of these, or 14oz. to 1 gallon, in order to replace the fat removed for butter-making, which can be done at one-half the cost. In other words, the nutritive value of milk-fat can be replaced by spending in farinacea half the sum realised by the sale of the butter.

Reckoning 5oz. as the yield in butter per gallon of milk, and 1s. 4d. per pound the selling-price, it will be evident that when new milk sells retail at 1s. 4d. the gallon, the skim-milk ought to be worth 11d. per gallon, seeing it only lacks the 5d. worth of milk-fat to make it of equal value to whole milk; and, further, if, as has just been stated, the nutritive value of this milk-fat can be replaced by the expenditure of half that amount in farinaceous foods, then the skimmed milk would thus be worth to the consumer 1s. 1½d. per gallon, or only 2½ less than whole milk.

In comparing the food-value of skimmed milk with that of the lean of meat some interesting facts are brought out.

It is apparent from this statement that the deficiency of albuminoids in skimmed milk, as compared with those contained in the lean of meat, may be made up by the expenditure of 1d. in oatmeal, which at the same time would supply the deficiency in fat five times over.

The total solids in a mutton-chop are slightly more than double those contained in a pint of skimmed milk, so that it would require about a quart of the latter to provide solids equal in quantity to those in a mutton-chop; but this quart of skimmed milk is procurable for 2d. at the most, or one-fifth the cost of the mutton-chop, whole milk supplying the same amount of solids at about one-fourth the cost of flesh-meat.