MAKING MILK POWDER

Te Awamutu Courier, Volume 53, Issue 3822, 16 October 1936, Page 9

MAKING MILK POWDER

ONE OF SCOTLAND’S NEW INDUSTRIES. Dairy farmers in this part of the Dominion will doubtless be interested in the following article by in the Weekly Scotsman, Edinburgh: Any new industry in Scotland is jf thei utmost interest, however large or small it may be. Especially is this so when the industry is itself a fairly new development and likely to extend with an increasing demand for its products. One such new industry is the, milk powder factory down at Kirkcudbright which was opened little more than a year ago. The manufacture of surplus milk requirements into such a milk product is of course largely the result of the arrangements made by the Milk Marketing Board. So that besides milk powder production we have in the West of Scotland quite a number of factories where milk is being processed in one way or another. But here we are concerned with the spray drying process of convertingliquid milk into milk powder. The process is in essence a fairly simple one; it is a case of spraying milk at high pressure into a chamber through which is passing a current of hot air which absorbs and carries off all the moisture from the milk. But various additional processes are added for the further refining of the product. In the first place an electric pump draws milk into three large storage tanks of 3000 gallons capacity, through stainless steel pipes. As in the usual dairy processes this milk is drawn off, passed through tubular heaters and pasteurised, afterwards flowing back into the storage tanks again. A COMPLICATED PROCESS. The next process is rather a complicated one. The milk passes into a liquid collector, where it is maintained at a constant level and is circulated through a heater. At the same time the saturated hot air which has been responsible for the production of the milk powder in a subsequent process is passed through it before being allowed to escape through an exhaust. This is not essential to the process but it an economy measure. The hot saturated air contains two things of value, first of all, a good deal of its original heat, and secondly, a small quantity of milk powder brought from the drying chamber. The purpose of passing it through the liquid collector is to get out of it both these valuable constituents. The heat is used in partly heating the tnilk in the collector, and the> milk powder is taken into solution by the milk circulating there. The milk in this collector then becomes a hot concentrated milk, which is pumped under, very high pressure through an atomiser into the drying chamber, where it comes in contact with the blast of hot air from the fans and heaters. The result is that it loses its moisture, almost instantaneously and falls as a fine snowwhite powder to the bottom of the drying chamber. From the drying chamber it is blown by high pressure air currents into a powder collector through a powder hopper and sifter into special paper-lined barrels. It is interesting to note that the whole of this process from the release of the milk from the storage tank to the final barrelling takes only about thirty seconds! EXACTING STANDARDS. There are one or two little points to be mentioned about the production of milk powder. In the first place the most exacting standards of cleanliness as may be expected, observed, and the whole machinery is designed for easy cleaning. In fact, all the milk lines are dismantled and washed at the end of each day’s run. The powder itself is completely soluble in water, and is of very fine granulation and colour. When reconstituted it has the advantage of retaining the flavour and odour of fresh milk, so that in many manufactured foods it is just as wholesome as fresh milk, and in addition cheaper and more convenient. It is finding an increasing scope in the production of bread and all bakery products, including biscuits and confectionery, as well as ice-cream, sausages, and so on. May we hope that from little beginnings there will grow greater things, and that Scotland will sec this milk powder factory duplicated and triplicated even in her dairy farming districts.