Globules of butter fat are suspended in the milk. They are surrounded
by films of adsorbed caseinates, albuminates, and globulinates. The fat
globules of milk are too large to form a permanent emulsion, so they grad-
ually rise to the top of the milk in the form of cream. If the milk or cream
is put through a machine called a homogenizer, the fat globules are reduced
in size. This is accomplished by using pressure and forcing the milk or
cream through small openings. Homogenized milk or cream may form a
stable emulsion if the fat globules are reduced enough in size. Hence, when
the fat is broken into fine enough globules the cream will not rise to the
top of the homogenized milk.
The size of the fat globules after homogenization depends upon the
temperature of the milk during homogenization and the pressure used.
With increase in temperature the degree of dispersion increases rapidly
from 40° to 65°C., so that the smallest fat particles are obtained at 65°.
Ordinarily temperatures above 65° are not used for homogenization. The
size of the fat particles also decreases with increased pressure.
Whipped cream is stabilized by proteins. The fat globules in cream
are surrounded by films of protein substances. Homogenized cream also
has the film of adsorbed proteins around the fat particles. Clayton states
the fat particles in homogenized cream may be 1000 times greater in
number than before homogenization. Since the number of fat particles is
WHIPPING CREAM 299
increased, the amount of globulinates, caseinates, and albuminates used in
forming films is very much greater, for the surface area of the fat globules
has increased enormously.
Whipped cream is both an emulsion and a foam. The fat particles must
be surrounded by a film of protein in order to be stabilized, and the air
globules must be surrounded by a film of protein to stabilize them. In
homogenized cream most of the protein is used in surrounding the fat
globules, on account of the increased surface area of the smaller and
increased number of fat globules, and thus there is not enough left to sur-
round the air bubbles. Hence, homogenized cream seldom whips unless
protein is added for film forming.
Factors that affect the whipping quality of cream. In addition
to the protein or film forming in whipping cream, the fat content, the size
of the fat particles, the temperature of whipping, and the viscosity are
important factors. Dahlberg and Hening have studied the relation of
viscosity, surface tension, and whipping properties of milk and cream. They
have found that increased viscosity increases the whipping properties of
cream, but the lowering of the surface tension does not improve the
whipping qualities. They have reported two changes taking place during
whipping. The incorporation of air depends upon the milk proteins form-
ing the film around the air globules, and the rigidity or stiffness of the
whipped cream depends upon the clumping together of the fat particles.
The best whipping cream did not give as large a volume as some other
creams, but it had less liquid drain out of it after whipping.
Cream whips better with an increasing fat content up to 35 per cent.
The cream with the higher fat content gives more particles for clumping
and also increases the viscosity of the cream.
Page 242
Presented as published in 1932. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
AI-modernized reading of the original text
A modernized reading is not available for this page yet. You are seeing the original text.
Globules of butter fat are suspended in the milk. They are surrounded
by films of adsorbed caseinates, albuminates, and globulinates. The fat
globules of milk are too large to form a permanent emulsion, so they grad-
ually rise to the top of the milk in the form of cream. If the milk or cream
is put through a machine called a homogenizer, the fat globules are reduced
in size. This is accomplished by using pressure and forcing the milk or
cream through small openings. Homogenized milk or cream may form a
stable emulsion if the fat globules are reduced enough in size. Hence, when
the fat is broken into fine enough globules the cream will not rise to the
top of the homogenized milk.
The size of the fat globules after homogenization depends upon the
temperature of the milk during homogenization and the pressure used.
With increase in temperature the degree of dispersion increases rapidly
from 40° to 65°C., so that the smallest fat particles are obtained at 65°.
Ordinarily temperatures above 65° are not used for homogenization. The
size of the fat particles also decreases with increased pressure.
Whipped cream is stabilized by proteins. The fat globules in cream
are surrounded by films of protein substances. Homogenized cream also
has the film of adsorbed proteins around the fat particles. Clayton states
the fat particles in homogenized cream may be 1000 times greater in
number than before homogenization. Since the number of fat particles is
WHIPPING CREAM 299
increased, the amount of globulinates, caseinates, and albuminates used in
forming films is very much greater, for the surface area of the fat globules
has increased enormously.
Whipped cream is both an emulsion and a foam. The fat particles must
be surrounded by a film of protein in order to be stabilized, and the air
globules must be surrounded by a film of protein to stabilize them. In
homogenized cream most of the protein is used in surrounding the fat
globules, on account of the increased surface area of the smaller and
increased number of fat globules, and thus there is not enough left to sur-
round the air bubbles. Hence, homogenized cream seldom whips unless
protein is added for film forming.
Factors that affect the whipping quality of cream. In addition
to the protein or film forming in whipping cream, the fat content, the size
of the fat particles, the temperature of whipping, and the viscosity are
important factors. Dahlberg and Hening have studied the relation of
viscosity, surface tension, and whipping properties of milk and cream. They
have found that increased viscosity increases the whipping properties of
cream, but the lowering of the surface tension does not improve the
whipping qualities. They have reported two changes taking place during
whipping. The incorporation of air depends upon the milk proteins form-
ing the film around the air globules, and the rigidity or stiffness of the
whipped cream depends upon the clumping together of the fat particles.
The best whipping cream did not give as large a volume as some other
creams, but it had less liquid drain out of it after whipping.
Cream whips better with an increasing fat content up to 35 per cent.
The cream with the higher fat content gives more particles for clumping
and also increases the viscosity of the cream.