DETECTION OF LIME USED IN" DAIRY PRODUCTS. 21 
All the butters, the analyses of which are given in Table 15, were 
alkaline to litmus to a greater or less degree, and had a peculiar foam 
test and a sweetish smell on heating, especially those of high lime 
content. When heated with dilute sulphuric acid all of them gave a 
more or less distinct smell of butyric acid, thus indicating the pres- 
ence of calcium butyrate. The water extracts of these butters were 
alkaline to litmus paper and those containing the larger quantities of 
calcium oxid were alkaline to phenolphthalein. Some of these sam- 
ples have been kept for months in an ice-box without developing the 
characteristic smell of rancid butter, although many became moldy 
and possessed a bad odor. When the butter was treated with hot 
alcohol, as in the determination of acids in fats, considerable acidity 
was usually found, indicating the presence of free oleic and palmitic 
acids. 
The liming of cream is a renovation of a deteriorated intermediate 
product, while the liming of butter is a renovation of a more or less 
spoiled final product. The chemistry of the two processes is differ- 
ent. The main acid constituent of sour cream is lactic acid, and when 
lime is added calcium lactate is probably the principal substance 
formed, but with an excess of lactic acid remaining. When this 
cream is churned the percentage of calcium oxid in the salt-free ash 
is increased because of the quantity of calcium lactate remaining in 
the butter fat. It is probable that with excessive washing these cal- 
cium salts could be washed out, but with the calcium would go the 
flavor, a property the creamery man desires to keep in his product 
as its value depends upon it, in large measure. Since the lime is 
never added in excess, the butter will give a more or less acid reaction 
to litmus paper. 
Storage butter is always acid even when not rancid. When it 
is placed in a lime solution the free water-soluble acids that may 
be present are neutralized to a greater or less degree. Since these 
acids are perhaps one of the main causes of bad odor in rancid 
butter, their neutralization will sweeten and deodorize the product. 
The nonvolatile, nonsoluble acids, oleic and palmitic, play only a 
secondary part in this process. These acids and their calcium salts 
are practically insoluble in water and would be neutralized only in 
small part. By using alcohol their presence in the free state can be 
demonstrated. The calcium salts of the offensive water-soluble vola- 
tile acids are more or less soluble in water and are removed partly 
in the subsequent washing, the amount which remains depending 
on the extent of the washing. Their presence can be demonstrated 
by their odor on adding dilute sulphuric acid. Nor is the excess of 
calcium hydroxid entirely removed, for all of the water extracts of 
these butters gave an alkaline reaction to litmus. When such butter 
