• Cream separation is a phenomenon by which
the milk is separated into cream and skim
milk by centrifugal force.
Formerly, the cream separation was
made by gravity method.
In 1880, C.G de Laval of
Sweden devised the
first mechanical cream
separator, based on the principle of
To obtain a fat-
reduced or fat-
milk fat for the
To standardize the
fat content of
To recover fat
Cream Separation is based on two
facts that :
Fat exists in poly-disperse system in an
The specific density difference
between milk fat (p = 0.93g/cm3) and
skim milk (p = 1.035g/cm3) is large .
When milk is allowed to stand undisturbed for some time ,
there is a tendency of fat to rise .
Being very slow, it is no longer used commercially
for cream separation .
The factors affecting the rate of rise of fat in
gravity method of separation are :
Size of fat
Five methods for separating the cream using
Shallow Pan Method : Milk is allowed to stand in a pan of 10 cm depth and 45-60 cm diameter at
7 degree Celsius for 24 hours .
Deep Pan Method : Milk is allowed to stand in pan of 20" depth and 8 to 12" diameter at 10
degree Celsius for 24 hours .
Water Dilution Method : Milk is diluted with water and allows standing for 12 hours at 37.7
degree Celsius temperature.
Scalding Method : Heating and cooling of milk slowly causes the formation of cream layer at
surface of milk .
Jersey Creamery Method : Milk is heated to 40 degree Celsius using hot water in the jacketed vat
and then cool to 10 degree Celsius using chilled water in place hot water in jacket of vat .
• When fat and skim milk are subjected to centrifugal force , the difference in
density affect the fat and skim milk that is ( heavier portion ) affected more
intensely than the fat (lighter portion )
• Centrifugal force is about 3000-6000 times more than gravitational force .
• The cream outlet is at higher level than skim milk outlet.
• Cream is channelized to the center.
Tubular bowl centrifuge
• Vertical cylinder, typically 0.1 - 0.15m in
diameter and 0.75 m long
• Feed liquor is introduced continuously at the
base of the bowl
• The two liquids are separated and discharged
through circular weir system into stationary
Disc bowl centrifuge
• Consist of conical bowl (0.2-
1.2m diameter) , which contains a stack
of inverted metal cones .
• Feed is introduced at the base of disc
• Better separation is obtained
by the disc bowl centrifuge due to
the formation of thinner layer of
Domestic cream separator
• Small capacity domestic cream separators
working on the principle of disc bowl centrifuge
• The separator is operated by hand with the help
of a handle fixed to it.
• Cream Separator - A Centrifugal Device -
#Animation - YouTube
• Cream separation process from milk -