748 ANNUAL REPORT OF THE Off. Doc. 



In the first place, we recognize nowdays two sorts of Pasteuriza- 

 tion as employed with dairy products, one which is designed to de L 

 stroy pathogenic or disease-producing organisms and one which 

 is aimed primarily at those which impair keeping qualities. The 

 lirst of these is meant to be a complete operation, the second, an in- 

 complete oue. Each has, however, a distinct and definite purpose. 

 Now it is only with the latter that the butter-maker has to do. His 

 subjection of large volumes of milk or cream to the influence of rela- 

 tively high temperatures for a short time in some one of the many 

 continuous forms of Pasteurizer improves but does not make per- 

 fect, gets rid of many but not of all the organisms. The more 

 modern mechanisms seem calculated rather to lessen the labor and 

 expense of handling a given volume of product than to insure the 

 death of all of the "bugs." For the distinct purpose in view, the en- 

 hancing of the keeping qualities of the butter, this is probably an 

 evolution in the right direction. 



A recent suggestion from a Western dairy school seems pertinent. 

 It is that the wash water should be Pasteurized. It often happens 

 — more often than not perhaps — that creamery water supplies are 

 not as pure, bacteriologically, as they should be. What avails it 

 for the buttermaker to Pasteurize the cream and then wash the but- 

 ter in a germ-laden water. To be sure he is not quite as apt to get 

 so large a variety of posies in his bouquet as if he used no effort to 

 improve the situation, but their numbers may be very great. At any 

 rate, experiments at the Iowa Station indicate that the keeping 

 quality of the butter was enhanced when the water was Pasteurized 

 as well as the cream. Filtering the water through stone, sand, coke, 

 charcoal and gravel also helps. 



Dairy salt serves four purposes in butter and cheese making: 



1. It aids in the expulsion of the butter-milk or whey. 



2. It augments the keeping qualities of butter. 



3. It serves to promote the ripening of cheese. 



4. It accentuates flavor. 



Nearly a million dollars' worth of dairy salt is used yearly, most 

 of it of domestic origin. Good salt does much and poor salt does 

 more to affect the grade of dairy products. How do the many sorts 

 offered us serve us? 



Salt is a combination of chlorin and sodium. But all salts are not 

 all salt. Indeed, no salt is all salt, as each brand carries more or less 

 impurity. The average American-made dairy salt carries 98.3 per 

 cent, of true salt and 1.7 per cent, of impurities, of which 6.2 per 

 cent, is moisture, 0.1 per cent, magnesium chlorid, 0.3 per cent, cal- 

 cium chlorid, and 1.1 per cent, calcium sulphate or gypsum. The 

 magnesium and calcium chlorids possess a bitter taste. In the 

 quantities ordinarily present they apparently exert no ill effects on 

 fresh butter, but they do sometimes damage storage goods. They 

 seem to incite a slow decomposition of the butter fat. The gypsum 

 is not only undesirable as a diluent but because it tends to cause 

 salt to cake. Other things being equal, a salt that is relatively free 

 from these impurities is to be preferred. Other things may not be 

 equal, however, for the size of the grain, its shape, its apparent 

 specific gravity and its solubility are important factors. The finer 

 the grain, the greater its weight in a given volume and tin 1 more 

 ready its solubility. Thus in a series of trials of fine and coarse 



