THE AGRICULTURAL JOURNAL. 



Dairying in Australia, 



THE HON. F. R. MOOR'S IMPRESSIONS. 



{Continued.) 



MILK TESTING. 



THE foUowiu'j; is a further instalment 

 of the pamphlet : — 



Short I>:; truotions. 

 There arc three vital points in milk 

 testing that must be recognised in 

 order to insure reliable results. The first 

 is to secure a proper representative sample 

 of the milk to be tested. The second is 

 to get a true sample from the composite 

 test bottle into the test flask. And the 

 third point includes careful attention to 

 all the remaining details of working. 

 Preparixg the Sample Bottles. 

 Composite samples give reliable results, 

 and save the trouble of daily testing. 

 Special graduated bottles are in the mar- 

 ket, and may be obtained very cheaply. 

 Rubber corks should be used, as they are 

 easily kept clean and sweet. Pure for- 

 malin is the most satisfactory preservative! 

 for keeping the samples. Four drops of, 

 formalin added with a medicine-dropper 

 is sufficient to put in the composite bottle. 

 The bottles should be thoroughly cleansed 

 after each testing is done. For use on 

 the farm, the names or numbers of the 

 cows can be attached to the neck of the 

 bottles, and at the creamery or factory 

 the name or number of the supplier can 

 be attached. 



Securing the Samples. 

 After a cow is milked, and the milk 

 weighed, poui it from one bucket into 

 another and tlien back before taking the 

 sample. Immediately afterwards take 

 some with a cup or measure, and put 

 some into the composite bottle. The 

 same quantity should be added each time, 

 and at the end of each week the bottle 

 will contain a representative sample of 

 the milk for that period. In a factory or 

 creamery the drip system is the most 

 reliable. 



Measuring the Test Sample. 

 The contents of the composite bottles 

 should be thoroughly mixed. If the 

 cream has set or is hard to mix, the bottles 

 should be placed in warm water, at a 

 temperature of 120 deg. for a few 

 minutes. The cream is then more easily 

 dissolved and mixed with the milk. A 

 bottle extender greatly facilitates the 

 mixing when the bottles are too full to 

 shake. The sample is measured with a 

 17.G c.c. capacity pipette, and put in the 

 test flask. To prevent spilling, the flask 

 should be held at an angle to allow the 

 air to escape. 



The Sulphuric Acid. 

 For milk-testing, sulphuric acid of 

 1.827 specific gravity is used. Special 

 hydrometers for ascertaining the 

 strength of the acid cost 3s. 6d. each, and 

 a glass jar for holding the acid Is. 6d. 

 When using the hydrometer the temper- 

 ature of the acid should be 60 deg. Fahr. 

 Never put a metal or wooden frame ther- 

 mometer in the acid, only glass or por- 

 celain vessels should be used. The acid 

 bottle should be kept corked when not 

 in use, as it absorbs moisture from the 

 air if exposed and becomes weak. The 

 acid and milk ought to be about 70 deg. 

 in temperature before mixing. It is 

 neglect of temperature and strength of 

 acid that causes a white curdy matter, or 

 a black charred substance, to appear in 

 the fat column. This temperature may 

 be secured by placing the test bottles in 

 a water bath of the desired heat after 

 measuring. The acid may be cooled or 

 heated in the same manner, but before 

 measuring. Altering the strength or 

 quantity of the acid is not recommended. 

 All bottles containing sulphuric acid 

 should have glass ground stoppers. The 



