WOMEN IN THE HOME

Press, Volume LXXIII, Issue 22111, 5 June 1937, Page 3

WOMEN IN THE HOME

MILK AS A FOOD Since so much publicity has been given in recent months to the value of milk as a food, the importance of it should be fully recognised. In emphasising the main fact, however, the contributing reasons may be overlooked. A hazy idea that milk is beneficial is hardly sufficient for an enlightened intelligence. Now and again it is a good thing to reason why. As a food, milk stands in a class quite by itself, since it contains more of the essential substances required toy the bony than any other single foou. Cooking does not greatly affect its ioocr value. The general analysis of good fresh milk is this:—B7 per cent, water, 3.5 per cent, protein, 4 per cent, tat, 4.5 per cent, lactose, and 0.7 per cent ash or mineral matter. The analysis does not mention the valuable vitamins, which are also present and whicn aad great vaiue to milk as a food.. “A pint of milk a day,” has become almost a slogan, and is the result of much careful research into the relation of food to health, more especially tnat of growing children. It has been proved that when milk is taken in sufficient quantities, there is a marked difference in the condition of the body. Without going into too many details, it is believed that a pint of milk a day. taken in one form or another, would supply the healthy adult with certain essential daily needs. One and a half pints is considered necessary for children. Of course, the daily ration may be consumed in various ways. A particularly good way is in cream soups, in which various vegetables may be added, to a thin white sauce. Another good combination is with fish or with whole cereals. Unsweetened condensed milk is a very useful food and when diluted as directed its food value is practically the same as that of fresh milk. Mineral Substances

The mineral substances while small in amount, are very important. It is a proved fact that for calcium salts, milk is the best source, particularly So because it is present in a form which .s easily assimilated by the body. Since calcium helps to build bone and testh it is essential in the diet of growing children. If it is not supplied by milk, it is very difficult to obtain the needs of the child’s body from other sources. At the same time, milk is a good source of phosphorus, and it is believed that where the calcium needs of the diet are adequately supplied, those of phosphorus will be met at the same time. Research has shown that in New Zealand there is a likelihood that the necessary calcium is not always supplied In sufficient amounts. If one pint of milk a day is used the supply is likely to be maintained, the extra ration being necessary for children. Milk is not as good a source of iodine as is edibleseaweed or fish, but it contains a small amount, and if enough milk is used during the day. a fair supply of thi vital substance is assured. So, if you adopt the slogan, you will have no further need to worry about the calcium or the phosphorus, for you will be getting both, and also a certain amount of iodine. Vitamins In the matter of vitamins, the fat of milk is known to be a good sourcof vitamin A. The fat is present in a very fine emulsified form, and the vitamin A contained in it adds greatly to its food value. This latter substance is necessary for growth and health and increases resistance to disease. When, by force of circumstances, skim milk is used, an ounce of butter in the daily ration would make a pint of skim milk practically equivalent to full milk. If butter cannot be afforded <:ome cod liver oil would supply the need. There is less of the vitamin known as B, in milk, than there is of that known as B2; both are important ; n the promotion of health and growth. The presence and importance of vitamin D is interesting in its relation to the assimilation of calcium and phosphorus. Vitamin D alone cannot take the place of either substance, but unless it is present, the bodv cannot make the best use of the calcium and phosphorus in the food. As all three are found in milk this again proves the case for its abundant use. Proteins

Proteins are obsolutely essential in the diet for the building up of tissues and repairing waste. Milk is the best source of what is called “first quality nrotein,” there being differences in the quality of proteins as in any other substance. It is believed that a quart of milk a day would supply all the building needs of the body, but that

would become monotonous, and therefore a tax on the digestive system. As other foods contain good proteins also, the balance is kept by using them by way of a change. The proteins contained in milk are called casein and lact-albumin. They are distinct substances. Every housewife knows both by sight, so to speak, as both are affected by familiar processes. The lact-albumin is coagulated or set by heat, and separates as a skin on the top of milk whrn it is heated, or on the top of milk puddings. Children and some adults dislike this skin, and so lose some of the food value. The * casein is affected by rennin or by acid. In clotting by rennet, as in the making of junket, or in the preparation of cheese, the casein is separated. and. with the fat, forms th. familiar white solid, which is soft at first, but becomes tough after standing. This process is analogous to the change which takes place when raw milk is taken into the stomach, when it is clotted by the action of the rennin in the gastric juice. Sometimes in digestive trouble it is n cessary to dilute the milk •with a diluent such as barley water or lime water, to reduce the density of the clot. Pasteurisation Souring of milk is caused by the action of lactic acid bacteria acting on the lactose or milk sugar, and converting it into lactic acid. _ This in turn acts on the casein, which if left long enough will separate. There is a certain difference between the clot and the curd, but in either case it is the protein which is affected. Sour milk, which is not stale, may be used in baking because of its acidity to replace partly the acid element in the raising, i.e., the cream of tartar. In pasteurisation, milk is heated to a temperature of 70 degrees C., and is kept at that temperature for 20 minutes, and then cooled rapidly. This treatment is based on the fact that rny pathogenic (disease-bearing) bacteria present are destroyed at this temperature. The lactic acid bacteria are not, and therefore the milk if kept may turn sour. In sterilisation the milk is heated to boiling point, kept at that temperature for some time, and then cooled rapidly. In this process all possible bacteria are killed, but the taste of the milk is very much changed also.