SEPARATING MILK

Hawke's Bay Tribune, Volume XIX, Issue 64, 2 March 1929, Page 12

SEPARATING MILK

AVOID DELAY. AND LOSS OF BUTTERFAT. Interesting work has been carried out at the Massey Agricultural College in connection with the most suit able temperature for the separation of milk, and the finding will probably save farmers considerable losses. In any case the nature of the work is drawing attention to the need for careful checking the fat content of skim milk, and if it does nothing else it should make farmers alive to the need for having the skim milk samples tested more frequently. It was found that tho temperature which gave tho smallest fat losses in the skim milk w’as 100 degrees F., and the losses becanic progressively larger as the temperature dropped, until at a temperature of 70 degrees F. they were quite considerable and sufficient to cause a loss of several hundred thousand pounds a year to tho dairying industry. Tho experiments showed that provided the milk were separated immediately after tho milking tho fat losses were not abnormal, but where part of the milk was being held aside it rapidly cooled, and reduced the temperature of all the milk in tho bowl, thus contributing to larger losses of fat. There are two ways in which the temperature can be kept up, and the advantages of these will be tested out thoroughly during later experiments. Hot water could bo added directly to the milk, or the milk could be put in a double jacketed pan and warmed from hot water in the outer jacket. There is some evidence to show that the addition of quantities of hot water redued the skimming efficiency of separators, so that meantime it would seem that the farmer’s best plan would be to rely on separating as soon as possible after the milk is drawn from the cow. The purchase of any apparatus for the heating of the milk would not be warrantee. ,

The experiments also’ showed that the state of lactation had some effect on separation losses, this being due to tho differences in the size of tho fat globules at tho various stages of tho lactation period. Warm cream should never be added to old, and when the two are mixed, after poling, tho cream should be thoroughly stirred with a metal stirrer. The wooden stirrer is undoubtedly a source of inferior cream, as it is seldom properly sterilised, and holds numberless iujurious germs. The metal tirrer is easily cleaned, and altogether more effective. Thorough stirring is essential, as still cream gathers gases that cannot escape if the stirfiifg is omitted.