14 CHEESE MAKING. 
On the other hand, the longer the period between milkings 
the larger will be the quantity cf milk given, and if the udder 
is not emptied it will become very much distended; from 
these facts it is argued that milk production is a continuous 
process, though the rate cf secretion may vary at different 
times. 
23. Cause of Bad Flavors. 
There are three causes for bad flavors in milk, namely: 
from strong-flavored feeds through the tlood, by absorption 
from the air, and by bacterial infection. 
24. From Feed Eaten. 
Some strong-flavored- feeds, like onions, turnips, cabbages, 
silage, rag weed, ete., put a like flavor into the milk given by 
the cow. The reader may have observed that when very hungry 
and faint, a little lunch will renew strength in a very few min- 
utes. This shows how quickly the food is taken into the blood. 
In a like manner, when a cow eats strong-flavored feeds, the 
volatile substances constituting the flavor are taken into the 
blood and from the blood they go into the milk. Aerating milk 
(81) will in a measure set these volatile substances free. If 
strong-flavored feed is given the cow just before milking, the 
flavor will be sure to be found in the milk. If fed just after 
milking, the flavors will probably pass out of the cow’s system 
before the next milking. 
25. Flavors by Absorption. 
Milk, especially when warm, will absorb odors through the 
medium of the surrounding air. It should therefore be kept 
away from the bad odors of hog pens, barnyards, swill barrels, 
and like odoriferous sources. It is very likely that the flavors 
of feed like turnips may get into the milk in this way. 
26. Bacterial Infection. 
Milk becomes sour upon standing. The souring is caused 
by the growth of minute organisms, commonly called microbes 
or bacteria. These are plants consisting of but a single cell and 
so small that they can be seen only by a powerful microscope. 
They increase very rapidly and by their growth produce the 
changes observed in the milk. Some forms change the milk 
