no MAINE AGRICULTURAL EXPERIMENT STATION. 



very closely the true hardness of the fat after it was congealed. 

 It was observed, however, that whenever the melting point of 

 the fat was low and the iodine number high, the butter was soft, 

 also that when the conditions were reversed, the melting point 

 high and the iodine number low the butter was hard ; and in all 

 cases when the iodine number was low, 30 or less, the hardness 

 of the butter corresponded very closely to the melting point of 

 the fat. 



A study of all available results of work by other chemists gives 

 still further encouragement that possibly these two determina- 

 tions together can be relied upon to indicate the texture. 



The manner of determining hardness employed in these 

 experiments cannot be called strictly scientific, but it is believed 

 that the figures given show more nearly the comparative hard- 

 ness, than any single chemical method employed. 



The figures given were obtained by thoroughly testing the 

 butter in a practical way. All the samples were carefully exam- 

 ined by means of pressure, cutting, etc., to determine their hard- 

 ness at temperatures ranging from 15° C. up to 25° C. ; also the 

 butter fats were placed side by side and tested in the same man- 

 ner, as they seemed to correspond very closely to the butter in 

 hardness. The opinion of the butter maker, on each lot as it 

 was manufactured, was also noted and taken into consideration 

 in making up the scale of figures. 



We find by inspection of the table that the average melting 

 point of the fats of the butters marked 6 in hardness is very 

 nearly the same as the fats of those marked 7 and 8 when, as a 

 matter of fact, the butters were so soft that they could hardly be 

 handled at ordinary temperature, and the fats were somewhat 

 liquid at a room temperature of 23° C. while the fats of those 

 marked 7 and 8 were quite hard at the same temperature. 



In manufacturing the butters every precaution was taken to 

 avoid variations in hardness, that could arise from physical and 

 mechanical causes by faulty manipulation. The method of 

 manufacture was as uniform as possible for all the periods, and 

 it is difficult to see how the variations in hardness could arise 

 from other than changes in the composition of the butter fat. 

 In fact some of the softest butters contained less water than the 

 hardest ones. " 



