56 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



METHODS OF COLLECTION. 



Two methods of collection are employed, viz., (a) purchase in open 

 market, and (b) from reliable dairymen. 



It is evident that by the first? method it will be easy to arrive at the 

 percentage of adulteration, especially when it is considered that these 

 purchases will be made in various parts of the country and under the 

 operation of several State laws bearing on the manufacture and sale of 

 butter surrogates. 



By the second method samples will be secured which will give accurate 

 data of the composition of genuine butter. 



This research at the present time acquires additional interest from 

 the fact that the manufacture of butter substitutes has reached in this 

 country large proportions, and seriously affects the interest of that 

 large class of our agricultural people who are engaged in the dairy in- 

 terest. Even if the butter substitute be as wholesome and palatable 

 as the genuine article, and if it be sold under its proper name, as is, in- 

 deed, generally the case, yet it tends to overrun the market and thus 

 cheapen the price of real butter. 



METHODS OF EXAMINATION. 

 WATER AND CURD. 



The content of butter in water varies within wide limits. This is due 

 to many causes, but chiefly depends on the treatment of the butter sub- 

 sequent to churning. It is the practice of some to " work" the butter 

 after churning only enough to roughly incorporate the salt. In this 

 way much water and curd are retained. Others wash the butter well 

 to remove the curd, and thus a butter poor in curd and rich in water is 

 obtained. Still others — and this is the proper method — wash well to 

 remove the curd, and then work well to remove the water, or expel the 

 latter in a centrifugal. This treatment produces a butter poor in water 

 and curd. The amount of water which a good butter should contain 

 should not exceed 12 per cent. 



In 19 butters, as seen by the following table, the highest percentage 

 of water is 14.31, and the lowest 7.34. 



ESTIMATION OF WATER. 



I have found this best done by using a flat dish of porcelain or plati- 

 num 6. c. m. in diameter. The bottom of the dish is covered with pure 

 sand to the depth of nearly 1 c. m. 



About 5 g. of butter are taken and the dish is heated in an air-bath 

 at 10U°-105° for two hours. If the fat is taken in bulk without sand it 

 is very hard to expel the last drops of water from the dish, but this can 

 be accomplished by stirring in a few c. c. of absolute alcohol. 



This latter method is to be preferred when it is desired to estimate 

 the curd in the Siwiie sample, as will be mentioned further along. 



It is too early yet in the investigation to fix a standard of water con- 

 tent which shall be the limit of a good butter. 



Foreign analysts have found in some instances the percentage of 

 water to be above 25. It is generally acknowledged by these chem- 

 ists that 12 per cent, water is a just limit beyond which a good butter 

 ought not to go. 



Perhaps it would be somewhat arbitrary to say that more water than 

 this would indicate a useful adulteration, but manufacturers should not 



