odors of various essential
oils and other odor-bearing substances. Under these conditions, the
cooler milk was tainted very much less than the milk at body temperature
even where the period of exposure was brief. It is therefore evident
that an exposure in the cow barn where the volatile emanations from the
animals themselves and their excreta taint the air will often result in
the absorption of these odors by the milk to such an extent as to
seriously affect the flavor.

The custom of straining the milk in the barn has long been deprecated as
inconsistent with proper dairy practice, and in the light of the above
experiments, an additional reason is evident why this should not be
done.

Even after milk is thoroughly cooled, it may absorb odors as seen where
the same is stored in a refrigerator with certain fruits, meats, fish,
etc.

~Distinguishing bacterial from non-bacterial taints.~ In perfectly fresh
milk, it is relatively easy to distinguish between taints caused by the
growth of bacteria and those attributable to direct absorption.

If the taint is evident at time of milking, it is in all probability due
to character of feed consumed, or possibly to medicines. If, however,
the intensity of the taint grows more pronounced as the milk becomes
older, then it is probably due to living organisms, which require a
certain period of incubation before their fermentative properties are
most evident.

Moreover, if the difficulty is of bacterial origin, it can be frequently
transferred to another lot of milk (heated or sterilized is preferable)
by inoculating same with some of the original milk. Not all abnormal
fermentations are able though to compete with the lactic acid bacteria,
and hence outbreaks of this sort soon die out by the re-establishment of
more normal conditions.

~Treatment of directly absorbed taints.~ Much can be done to overcome
taints of this nature by exercising greater care in regard to the feed
of animals, and especially as to the time of feeding and milking. But
with milk already tainted, it is often possible to materially improve
its condition. Thorough aeration has been frequently recommended, but
most satisfactory results have been obtained where a combined process of
aeration and pasteurization was resorted to. Where the milk is used in
making butter, the difficulty has been successfully met by washing the
cream with twice its volume of hot water in which a little saltpeter has
been dissol