ngent
in butter-making. While a cooked taste is imparted to milk or even cream
at about 158 deg. F., it is possible to make butter that shows no
permanent cooked taste from cream that has been raised as high as 185
deg. or even 195 deg. F. This is due to the fact that the fat does not
readily take up those substances that give to scalded milk its peculiar
flavor.

Unless care is taken in the manipulation of the heated cream, the grain
or body of the butter may be injured. This tendency can be overcome if
the ripened cream is chilled to 48 deg. F. for about two hours before
churning. It is also essential that the heated cream should be quickly
and thoroughly chilled after being pasteurized.

The Danes, who were the first to employ pasteurization in butter-making,
used, in the beginning, a temperature ranging from 158 deg. to 167 deg.
F., but owing to the prevalence of such diseases as tuberculosis and
foot-and-mouth disease, it became necessary to treat all of the skim
milk that was returned from the creameries. For this purpose the skim
milk is heated to a temperature of 176 deg. F., it having been more
recently determined that this degree of heat is sufficient to destroy the
seeds of disease. With the use of this higher temperature the capacity of
the pasteurizing apparatus is considerably reduced, but the higher
temperature is rendered necessary by the prevailing conditions as to
disease.

When the system was first introduced in Denmark, two methods of
procedure were followed: the whole milk was heated to a sufficiently
high temperature to thoroughly pasteurize it before it was separated, or
it was separated first, and the cream pasteurized afterwards. In the
latter case, it is necessary to heat the skim milk after separation to
destroy the disease organisms, but this can be quickly done by the use
of steam directly. Much more care must be used in heating the cream in
order to prevent injury to the grain of the butter. In spite of the
extra trouble of heating the cream and skim milk separately, this method
has practically supplanted the single heating. With the continual spread
of tuberculosis in America the heating of skim milk separately is
beginning to be introduced.[169]

~Use of starters in pasteurized and unpasteurized cream.~ In order to
secure the beneficial results presumably attributable to the use of a
starter, natural as well as a pure culture, it should be employed in
cream in which the bacteria have