2. • Anhydrous milk fat and butteroil are products
consisting of more or less pure milk fat.
• Although they are modern industrial
products, they have ancient traditional roots
in some cultures.
• Ghee, a milk fat product with more protein
and a more pronounced flavor than AMF
3. • Anhydrous Milk Fat must contain at least 99.8 %
milk fat and be made from fresh cream or butter.
No additives are allowed, e.g. for neutralisation
of free fatty acids.
• Anhydrous Butteroil must contain at least 99,8 %
milk fat, but can be made from cream or butter of
different ages. Use of alkali to neutralise free fatty
acids is permitted.
• Butteroil must contain 99,3 % milk fat. Raw
material and processing specifications are the
same as for Anhydrous Butteroil.
4.
5. Principles of production
• Production of AMF principally takes place
according to two methods:
continuous flow direct from cream
and from reworked butter
6. Manufacture of AMF from cream
• Pasteurised or non-pasteurised cream of 35 –
40 % fat content enters the AMF plant via the
balance tank (1)
• Routed via the plate heat exchanger (2) for
temperature adjustment or pasteurisation
• Centrifuge(4) for pre-concentration of the fat
to about 75 %.
7. • The temperature at preconcentration
and downstream to the plate heat exchanger
(11) is maintained at approx. 60 °C.
• The “light” phase is collected in a buffer tank
(6) to await further processing while the “heavy“
phase, typically called buttermilk, can be
passed through a separator (5) for recovery of
fat which will then be mixed with incoming
cream (3).
8. • The skimmed buttermilk goes back to the
plate heat exchanger (2) for heat recovery and
then to a storage tank.
• After intermediate storage in tank (6), the
cream concentrate is fed to a homogeniser (7)
for phase inversion (disruption of the fat
globules to release the fat), after which it is
passed through the final concentrator (9).
9. • concentrator the product is separated into a light
phase with 99,5 % fat and a heavy phase, with a
substantial amount of fat, which is returned to the
process via balance tank (3)
• As the homogeniser operates at a slightly higher
capacity than the final concentrator, the surplus
product not caught by the concentrator is recirculated
to the buffer tank (6).
• Part of the mechanical energy used in the
homogenisation process is converted into heat; to
avoid disturbing the temperature cycle of the plant,
this surplus heat is removed in the cooler (8).
10. • Finally, the oil consisting of some 99,5 % fat is
pre-heated to 95 – 98 °C in a plate heat
exchanger (11) and routed into a vacuum
chamber (12)
• To obtain a moisture content not exceeding
0,1 %, after which the oil is cooled(11) to
approx. 40 °C, the typical packing temperature
14. • Polishing
• Polishing involves washing of the oil with water to
obtain a clear, shiny (bright) product.
• 20 – 30 % water is added to the oil coming
from the final concentrator
• The water temperature should be the same as
the oil temperature.
• After a short hold, the water is separated out
again, taking water-soluble substances (mainly
protein) with it
15. Neutralisation
• Neutralisation is performed to reduce the level of
free fatty acids (FFA)present in the oil
• High levels of FFA give rise to off-flavours in the
oil
• Alkali (NaOH) at a concentration of 8 – 10 % is
added to oil in an amount corresponding to the
level of FFA.
• After a hold of around 10 seconds, water is added
in the same proportion as for polishing,
• the saponified FFA is separated out together with
the water phase.
16. Fractionation
• Fractionation is a process where the oil is
separated into high-melting and low-melting fats.
• These fractions have different properties and can
be used in various products
• The AMF, often polished to obtain the highest
possible degree of purity in the “raw oil”,
• melted and then cooled slowly to a calculated
temperature
• the specified fraction crystallises out while
fractions with lower melting points remain liquid.
17. • The crystals are harvested with special filters.
• The filtrate is then cooled to a lower
temperature at which other fractions
crystallise and are harvested
18. Decholesterolisation
• Decholesterolisation is a process in which
cholesterol is removed from the AMF.
• A frequently used method is to mix the oil with a
modified starch, betacyclo dextrine
(BCD).
• The BCD molecule surrounds the cholesterol and
forms a precipitate, which can be separated out
by centrifugation.
19. • Packaging
• AMF is filled in containers
• an inert gas, nitrogen (N2), is first injected in the
container.
• the N2 gas is heavier than air, it sinks to the
bottom
• When filling the AMF –which is heavier than N2 –
the AMF will sit underneath and the N2 gas will
create an “air-tight lid”, preventing the AMF from
air-induced oxidation.
