The yields of cream from milk, and butter from cream, are subject to much variation. The richness of milk differs too at morning and evening. But the average figures are approximately these:—12 qt. of milk should give 1 qt. of cream, and 1 qt. of cream should afford 14 oz. of butter. Morning milk is richer than evening milk, and the last portion drawn from the cow at each milking, is richer than the first. Autumn milk is best for butter, summer milk for cheese.
Milk to be sold fresh as such should be cooled immediately it is drawn from the cow, because while warm and exposed to the air, the sugar present undergoes oxidation with consequent liberation of lactic acid, which is indicated by the milk turning sour. When promptly cooled, milk can be kept sweet and transported without risk, besides which it gives up its cream more readily. The Americans have introduced various coolers, all of which are more or less effective.
As fast as brought in, the milk should be run through a hair sieve. This, and also the vessels with which the milk comes in contact, must be kept scrupulously clean by the aid of constant scalding, to be followed by rinsing with cold water, and drying in the air. The milk is exposed in the pans for varying periods in order that the globules of fat may have an opportunity of separating from the milk and floating on the surface. This process is now very commonly replaced by the use of a hydro-extractor, in which centrifugal action breaks up the milk into cream and “skim milk” without any need for waiting. According to the older practice the milk is left to stand for a considerable time, but no advantage is gained by exceeding 24 hours; in fact the best authorities say that it should be skimmed before the surface begins to look wrinkled, as this appearance is a symptom of incipient putrefaction. Large shallow perforated tin ladles are used for removing the cream, which should be carefully deposited, without splash, in white stoneware jars holding 2 to 12 gal., according to the size of the dairy. Common glazed earthenware is to be avoided on account of injurious chemical action. Skimming should be done twice daily, and each time an addition of cream is made to the jar the whole contents should be well but gently stirred with a stoneware spoon. The jars should be covered with gauze to exclude insects. In some dairies skimming is avoided by the simple plan of having a hole in the bottom of the milk dish by which the milk is drawn off, leaving the cream undisturbed.
Butter consists of the fatty portion of the milk, which is separated by the process known as “churning,” the object of which is to rupture the envelopes which hold the fatty matter. The bulk of this fatty matter resides in the cream. Butter may be “made” by churning either the milk or only the cream; and these may be either in a sweet or sour (“lappered”) state. The most general practice is to churn the cream alone in a lappered condition. For this reason the cream is set to ripen in stoneware jars for several days, averaging about 3 days in summer, and 5 or 6 in winter, preferably with occasional stirring. It is the general opinion that to get the best butter, the operation of churning should be comparatively slow, from ¾ hour to 2 hours—an hour being a fair average, varying, however, according to the season; the operation being much more tedious in winter than in summer. After the butter is separated from the cream, the buttermilk remains, containing the casein, salt, and sugar present in the original cream, though a portion of these is taken up with the butter. The greater the proportion of casein left in the butter, the poorer is the latter in quality, and the more readily will it become rancid.
Commenting on Jenkins’ pamphlet, ‘Hints on Butter-making,’ the Field recently published the following remarks:—
“Cheese-making, owing to American importations, has recently been so unprofitable that there is the more necessity for attention to butter-making. Why should the dairies of France, Holland, Denmark, and Sweden be able to supply an article in our markets which is superior to the bulk of our own make? And why, above all, in the matter of fresh butter, should Normandy be preferred by our large purveyors to the home dairies, were it not that by superior cleanliness and systematic management the quality is more dependable? For instance, we have been told that the manager of the Midland Hotel at Derby obtains all his butter from Normandy, because he finds it more reliable and of better and more uniform quality than English produce, notwithstanding that he lives in the centre of a great dairy district, and that the foreign produce is liable to deterioration by the journey. Here, then, the English farmer has an opportunity which he is very wrong to neglect. Cheese does not pay—at least, such varieties as are usually made; the demand for milk is limited; but good sweet butter will always command a fair and often a very high price. The reasons given by Jenkins for the inferior butter are these: That the milk is not skimmed early enough—often not before a certain amount of sourness has been developed in the milk, and an appreciable amount of curd has therefore become mixed with the cream. It is true that this curd increases the quantity, but it affects the quality; the butter becomes rank, and fetches a low price. Careless skimming, by taking off some of the milk with the cream, causes the same results. Carelessness in churning or in the manipulation of the butter, by which buttermilk and water are left in the butter. It may be that this is sometimes intentional, as more weight is obtained; but the quality is greatly injured. Much handling of the butter in making up is also a source of injury. Dirt in any form, bad smells, unskilful milking, bad food and water given to the cows; bad water, soap, or other noxious substances used in washing the dairy and vessels, are all causes of bad butter which must be guarded against. Temperature being allowed to vary, bad packing, &c., are all elements that require more care than is usually bestowed. As regards the food, Jenkins points out that in a wet season, grass alone cannot be depended on to give a good result—it is too succulent in its nature, and should be modified by the use of 4 lb. of bean meal given to each cow daily; whilst under ordinary circumstances the ration may consist of 2 lb. to 3 lb. of decorticated cotton cake, or 2½ lb. of bran and 2½ lb. of oatmeal, or 3 lb. of oatmeal and 2 lb. of bean meal. And he states, what all who have had experience will confirm, that by the use of such food more cows can be profitably kept, and that a farmer should look upon grass and hay as the most expensive articles of food. Then Jenkins proceeds to describe the process of butter-making adopted in the best districts of Normandy. We shall make no apology for publishing these directions verbatim, as we shall thereby assist the society in the dissemination of useful knowledge.
“1. Clean all dairy utensils by rinsing them with clean cold water, and afterwards scrubbing them with boiling water; after which repeat the cold rinsing.
“2. Cool the milk directly it is brought into the dairy by placing the cans in a running stream, or by any other available method. This, we may be permitted to observe, whilst most desirable, is often not easily attainable. The Americans, in selecting the site for the dairy, always prefer the base of a hill, so as to secure two very important factors—shelter from the sun and a cold spring of water. If running water cannot be obtained, that from a deep well may be used.
“3. Set the milk at a temperature of not exceeding 55°F. in glazed earthenware or tin pans. The question of whether these shall be shallow or deep will depend upon our facilities for reducing the temperature. If we have running water or ice, there is no doubt that the deep cans thus surrounded offer a greater surface of milk to the cooling influence, and this rapid and regular cooling causes the cream to rise freely and quickly; but if we have not these facilities, then shallow pans are preferable.