No. 6. DEPARTMENT OF AGRICULTURE. 203 



io contact with the other constituents of butter, it dissolves more 

 easily in acetic acid and in alcohol, the solvent employed in the 

 Valenta and Crismer tests respectively. 



The fat of a renovated butter naturally exhibits most, if not all, 

 of the ear-marks of a raucid butter, especially the high acidity and 

 low Valenta or Crismer number and usually, a low volatile acid num- 

 ber. When freshly made it differs from rancid butter in possessing 

 less of the disagreeable odor and flavor which rendered the rancid 

 article unsalable; no satisfactory chemical measure of the differ- 

 ence between renovated and rancid butters io the quantities of alde- 

 hydes they contain, has yet been found. Until recently, renovated 

 butters have exhibited a distinct tendency to sputter like oleomar- 

 garine when melted, and to crystallize as the result of their heating 

 aod cooling; but these characteristics are less possible in many 

 samples of late make. 



Doolittle and Hess have suggested that, since renovated butter is 

 commonly rechurned out of whole milk or skim-milk, it will usually 

 contain more albumen than butter churned from ripened cream. 

 This difference is sometimes exhibited in such degree as to form a 

 positive meaiis of identification of the renovated butter, but not in 

 all cases. 



In the absence of chemical tests conclusive in all cases, the diffi- 

 culty of a perfect control of the commerce in renovated butter by the 

 usual methods of regulation is clearly apparent and the need is 

 evident if keeping a record of the manufacture and distribution of 

 this commodity. 



Concerning the effect of renovated butter upon health, there are 

 few recorded dates. Most persons experience more or less nausea 

 upon the use of strongly rancid butter, and Arata found that very old 

 butter produced vomiting, pain of the bowels and purging. How far 

 these ill-effects are reduced by renovation has not been determined 

 by exact test. The commonly noted lack of care to prevent the 

 contact of the rancid butter used for renovation from filth and exces- 

 sive decay, constitutes a fair ground of question as to the wholesome 

 nature of the article made therefrom by a purely mechanical method 

 of renovation. The temperature at which butter melts is entirely 

 too low to secure the sterilizatioo or even the pasteurization of the 

 melted fat. 



The sale of decayed or decomposed foods has not been so prominent 

 as to call for special notice. Abuses of this kind are often so appar- 

 ent as to be self-regulating, as in the case of rotten vegetables, 

 tainted meats or ''swell-head" canned goods. So far as diseased 

 meats are concerned, the services of the veterinarian rather than the 

 chemist are required to prevent their reaching the market; the same 

 is true of the prevention of the sale of milk from diseased animals. 



