Butter, the fat of cow's milk, which after separation in the form of Cream (q.v.) from the watery portion, has by means of agitation been made into a solid greasy mass; the action of the churn (see CHURNS) breaking the outer skin of the butter globules, and thereby enabling them to adhere closely together, in place of floating about in the milk, or remaining as cream.
By the ancients butter was used as an ointment for the skin, and in Southern Europe, even now, it is rarely taken with food. Olive-oil is there a more natural and more common product for supplying the fat necessary for food purposes.
The separation of Cream (q.v.) having been accomplished, butter may be churned immediately, though the operation would probably be prolonged. The usual method is to set the cream to 'ripen,' to induce a condition of incipient acidity through the production of Lactic Acid (q.v.), by keeping it at a temperature of 60° F. for twelve hours, stirring being frequently resorted to, to prevent clotting, and to preserve uniformity of character in the cream, with the object of securing uniformity in the butter. It is important that a thermometer should be used to determine temperatures. The average temperature at which cream is churned is 60° F. In summer during hot weather this may be with advantage reduced to 55° or 56°, while during frost it may be raised to 65°, or in ordinary winter weather 62° to 63°. If these figures are adopted, the temperature during the operation will rise a few degrees in hot weather, and fall slightly when the temperature of the atmosphere is low. Heating should be done by placing the vessel containing the cream in a hot-water bath. This, and constant stirring of the cream while heating is proceeding, secure uniform heating, and prevent the injury to texture resulting from scalding a part of the cream in contact with the side of the vessel. When everything is in proper condition, in about thirty minutes the cream ought to 'break' in the churn, and the butter collect in a granular form; the small pieces being about as large as wheat grains. The Butter-milk (q.v.) is then strained off, and a small quantity of pure cool water put into the churn in place of it, sufficient to wash off the most of the buttermilk remaining. The second washing is done to cool, and thereby consolidate the butter, which is at first soft, more especially in warm weather. A plentiful supply of water is required, and to it may be added a little salt. The third time water is added it is in small quantity sufficient to float the butter, so that it may be easily removed from the churn. After this butter should be worked as little as possible to prevent injury to its granular texture, which for marketing purposes is one of its most important qualities. On account of the injury done to the texture of butter by the various mechanical 'butter-workers' used to press the water out of it, these workers have in recent years found less favour.
In any case butter should be as little as possible touched by the hand, and that only when it is cold and quite clean. If milk is left in the butter, it soon becomes rancid and offensive both to taste and smell. Butter may be made to keep good for a longer or shorter period by adding salt, which must be pure dairy salt. Ordinary salt retailed by small grocers often contains impurities, such as salts of magnesia, which give a bitter taste and bad smell to butter, if mixed with it. Salt may be incorporated with butter by washing it with a thick brine. 'Powdered' butter is made by working finely divided dry salt, oz. to 1 lb. of butter, into it. The name 'salt' butter is used when 1 oz. per lb. has been added. So as to insure the proper mixing of the salt, the butter should be allowed to lie for a few hours before the working is completed.
'Fresh' butter, to which salt has not been added, has a peculiarly rich flavour immediately after coming from the churn. This flavour varies considerably with the condition of the cream as regards ripeness or acidity before churning. Sweet-cream butter from sweet cream does not give a full flavour, and it does not keep so long. Rancid cream produces a bad flavour in the butter, due largely to the presence of Butyric Acid (q.v.). It is also inferior in keeping qualities. Butter from moderately ripe cream has a fine flavour, and, when well made, it ought to remain good and sweet for a week. But the butter which has the fullest and finest flavour of all is that made from cream churned when at an advanced stage of ripeness. Such butter should be eaten within a day, or two days, of its churning, as its keeping qualities are defective.
Butter made from the milk of cows feeding on grass or sweet silage is of a yellow colour, which deepens with the richness of the pasture. Cows kept in the house on hay or dry food, give white and inferior butter. Cows that have been many months calved yield pale butter; and, besides, such butter is more difficult to churn, on account of the butter globules being small. Annatto (q.v.) is frequently used, being put into the churn, to give a colour corresponding to that of good grass butter. The juice expressed from a carrot which has been rasped down serves the purpose in the country, if the butter is to be consumed within a few days; but after a time it injures the keeping qualities by decaying.
The butter made from the milk of the Indian Buffalo (Bos bubalus) is extremely pale and insipid. In India, on account of the extreme heat, butter does not keep, and for Anglo-Indians it is usually made each morning by the native servants shaking the cream in a bottle. It has been suggested that butter-making is an oriental invention, and may have been first obtained by Arabs who carried milk in skin-bottles on the backs of camels, which in walking gave the necessary churning motion.
Tinned salt butter of excellent quality is also sent from Europe to India. Butter of native Indian manufacture, if intended to be kept, is boiled or clarified, and then it assumes the name of Ghee (q.v.), which is largely used in native cookery and the manufacture of sweetmeats. Though butter has been locally used from the very earliest periods of which records exist, yet it is only within recent years that it has become to a great extent an article of international commerce. Ireland makes much excellent butter. Britain imports it largely from America, and also from the Continent—Holland, France, and Denmark. In 1894, 2,574,835 cwt. of butter, worth £13,456,699 (including Australian butter), were imported into the United Kingdom.
Butter-making in America is carried out mostly in butter-factories or creameries. These were instituted on account of the difficulty of attaining good results in small establishments under the influence of a climate which is less favourable than that of Great Britain for the manufacture of milk into butter or cheese. By adopting the co-operative principle farmers can afford to employ the best trained operators, and purchase the best machinery and appliances for securing a uniformly good sample, representing a large bulk, which ultimately becomes known in the market, and thereby secures more than an average price. Margarine-factories are very generally associated with butter-factories, and another part of the work of many of the latter is the manufacture of skim-milk into cheese, after adding some pure oil to it to make up for the loss of butter fat.
Butter-factories have become more numerous in this country and in Ireland within recent times. Centrifugal separators are used to remove the cream from the milk as soon as possible after it comes from the cow. The skim-milk is thus got sweet and fresh, and is sent without delay to the large town centres, and there sold to the working-classes cheaper than new milk. The cream is churned when sufficiently ripe, and before it becomes sour, which it is extremely liable to do during sultry weather under the old method of raising it by setting the milk in flat vessels. The parcel post is now taken advantage of by certain factories to send daily supplies of fresh sweet butter to all parts of the country. The establishment of butter-factories throughout the country will tend greatly to improve the quality of butter produced. See the articles CHURN and DAIRY; also L. B. Arnold's American Dairying (New York, 1877), Sheldon's Dairy Farming (1879-81), and J. B. Harris's Cheese and Butter Maker's Handbook (1885).
BUTTERINE is a substance which, when well made, cannot be distinguished from good butter except by chemical analysis. The substitution of it for pure butter had grown to such an enormous extent in Great Britain, that it was found necessary to prohibit its sale under this name, by act of parliament in 1887. It is now sold as Margarine, or Oleo-Margarine, and may be regarded as a valuable adjunct to the food of the labouring-classes. It is made with great care and skill from the finest ox-fat, which is passed through an elaborate and highly scientific process of purification. It is then mixed with a varying proportion of real butter, and flavoured by washing with milk, and finally marketed in large quantities in a beautiful uniform condition. It is largely manufactured in America, as also on the Continent, and to a limited extent in Great Britain, which in 1886 imported 887,974 cwt. of it. In 1894 the import had increased to 1,109,325 cwt., worth £3,044,810. See German works on artificial butter by Mayer (1884), Sell (1886), and Wollny (1887).
BUTTERMILK is the residue of cream after the butter has been removed by churning. It forms a wholesome and agreeable as well as a nourishing drink in hot weather. It possesses the slightly acid taste from the acidity developed in ripening the cream. In composition it retains the ash ingredients, casein, and sugar of ordinary milk, while, on account of small particles of butter being left in it, it is not devoid of fatty matter. When the whole milk is churned, the resulting buttermilk is inferior both in taste and quality. It would be very valuable if sold at a low price to the poor people in the slums of our large cities. In the country districts of both Ireland and Scotland it is commonly taken with porridge or potatoes. Buttermilk is light and digestible, and is used as a beverage in the treatment of certain diseases.